Examkin

Logical Reasoning

666 soru

Tüm türler666Çoktan seçmeli343Çoklu seçim54Doğru / Yanlış70Eşleştirme166Sıralama18Boşluk doldurma10Kısa cevap5
Soru 121Soru →

Public Health Researcher: A recent observational study monitored municipal road-resurfacing crews routinely exposed to concentrated asphalt vapor and found that they exhibited significantly higher concentrations of systemic inflammatory biomarkers than municipal administrative workers. Because both cohorts demonstrated comparable baseline sleep patterns, nutritional profiles, and self-reported psychological stress, the researchers concluded that prolonged inhalation of asphalt vapor directly triggers this systemic inflammatory response.

Which of the following, if true, most seriously weakens the public health researchers' argument?

Cevabı ve açıklamayı göster

Cevap: The road-resurfacing crews regularly operated heavy pneumatic tampers and vibratory compactors, tools whose prolonged mechanical vibration is independently known to trigger elevated systemic inflammatory biomarkers.

Cevap

The finding that road-resurfacing crews regularly operate pneumatic tools whose mechanical vibration independently triggers systemic inflammation most seriously weakens the argument.
The correct choice introduces an alternative explanation for the elevated inflammatory biomarkers observed among road-resurfacing workers. The author's argument relies on a causal inference: because road crews had higher biomarkers than office workers with similar sleep, diet, and psychological stress, asphalt vapor must be the cause. Demonstrating that road crews were simultaneously exposed to another distinct condition—mechanical vibration from heavy pneumatic equipment—that independently induces systemic inflammation undermines the conclusion that asphalt vapor is the causal agent.

Adım Adım Çözüm

1
Identify the conclusion and supporting premises of the argument.
Premises: Road crews exposed to asphalt vapor have higher inflammatory biomarkers than office workers with similar sleep, diet, and psychological stress. Conclusion: Asphalt vapor inhalation directly triggers this systemic inflammatory response.
Isolating the core premises and conclusion clarifies the causal claim.
2
Determine the logical gap and implicit assumption.
The author assumes that because sleep, nutrition, and psychological stress were controlled, no other confounding factor unique to road crews could account for their elevated inflammatory biomarkers.
Causal arguments on the LSAT frequently overlook alternative causes for an observed correlation.
3
Evaluate the options to identify new information that provides a plausible alternative cause or exposes the unstated assumption.
The option establishing that road crews operate vibrating pneumatic machinery—a known independent cause of systemic inflammation—provides an alternative explanation for the elevated biomarkers, breaking the direct causal link to vapor inhalation.
Providing an unconsidered alternative cause for the effect directly undermines a causal conclusion.

Anahtar Kavram

Weakening Causal Arguments via Alternative Explanations
Tahmini Süre:2m 0s
Soru 122Soru →

Organizational Psychologist: A study tracked twenty mid-sized technology firms that replaced assigned private cubicles with unassigned, open-plan workstations. Over the subsequent two years, documented collaborations between employees from different functional departments increased by thirty percent. The researchers concluded that eliminating assigned seating directly increased interdepartmental collaboration by encouraging spontaneous daily interactions among employees who otherwise would not meet.

Which of the following, if true, most seriously weakens the organizational psychologist's argument?

Cevabı ve açıklamayı göster

Cevap: The firms transitioned to unassigned workstations as part of a broader corporate restructuring that mandated cross-departmental project teams for all major product initiatives.

Cevap

The statement showing that the firms adopted unassigned workstations concurrently with a corporate restructuring that mandated cross-departmental teams directly undermines the conclusion by introducing an alternative cause.
The correct response introduces an alternative explanation for the thirty percent increase in cross-departmental collaborations. If the firms simultaneously enacted a restructuring that explicitly mandated interdepartmental project teams, this corporate requirement—rather than spontaneous daily interactions enabled by open-plan seating—is likely responsible for the documented increase. This severs the inferred causal connection between the physical seating layout and the collaborative outcome.

Adım Adım Çözüm

1
Analyze the argument's structure and identify the conclusion and premises.
Premise: Moving to unassigned workstations correlated with a 30% increase in interdepartmental collaborations. Conclusion: The seating change directly caused the increase via spontaneous interactions.
Weaken questions require identifying the exact causal gap between the evidence (correlation) and the author's claim (causation).
2
Identify the primary flaw or underlying assumption in the author's reasoning.
The author assumes that no other concurrent policy or confounding factor was responsible for the increase in cross-departmental collaborations.
Causal conclusions are vulnerable to alternative explanations, reverse causation, or third-variable confounders.
3
Evaluate the answer choices to find the one that introduces an effective alternative cause.
The finding that the workstation change was part of a company-wide restructuring requiring joint project teams provides a direct alternative explanation for the rise in collaborations.
Demonstrating that an institutional mandate occurred simultaneously undermines the claim that seating-induced spontaneous interactions were the cause.

Anahtar Kavram

Causal reasoning and alternative explanations in Logical Reasoning arguments
Tahmini Süre:1m 15s
Soru 123Soru →

Archaeological metallurgists studying Early Bronze Age tools have established the following facts regarding a collection of recovered Aegean metalwork:

• Every arsenic-bronze dagger that exhibits a dendritic crystalline microstructure was cast using an open stone mold.
• No artifact cast using an open stone mold was alloyed with imported tin from Central Asia.
• Most arsenic-bronze daggers recovered from the Cycladic burial complex were alloyed with imported tin from Central Asia.
• Any artifact that was not alloyed with imported tin from Central Asia exhibits localized surface oxidation.

If the statements above are true, which one of the following must also be true?

Cevabı ve açıklamayı göster

Cevap: At least some arsenic-bronze daggers recovered from the Cycladic burial complex do not exhibit a dendritic crystalline microstructure.

Cevap

At least some arsenic-bronze daggers recovered from the Cycladic burial complex do not exhibit a dendritic crystalline microstructure.
The deduction follows strictly from combining the quantifier statement with the conditional contrapositives. We are given that most Cycladic arsenic-bronze daggers contain imported tin. The second premise states that open stone mold casting precludes imported tin; its contrapositive means that any artifact with imported tin was not cast in an open stone mold. The first premise establishes that having a dendritic microstructure requires open stone mold casting; its contrapositive ensures that an arsenic-bronze dagger not cast in an open stone mold cannot exhibit a dendritic microstructure. Combining these steps guarantees that the majority of Cycladic arsenic-bronze daggers lack a dendritic microstructure, which fully validates the claim that at least some do not.

Adım Adım Çözüm

1
Symbolize the formal conditional relationships and quantifiers from the premises.
Premise 1: (Arsenic-Bronze Dagger AND Dendritic Microstructure) → Open Stone Mold. Premise 2: Open Stone Mold → NOT Imported Tin. Premise 3: Most Cycladic Arsenic-Bronze Daggers → Imported Tin. Premise 4: NOT Imported Tin → Surface Oxidation.
Clarifies the logical dependencies and chainable terms without extraneous narrative detail.
2
Derive the contrapositive of Premise 2 and connect it to Premise 1.
Imported Tin → NOT Open Stone Mold. By contrapositive of Premise 1: (Arsenic-Bronze Dagger AND NOT Open Stone Mold) → NOT Dendritic Microstructure. Therefore, for any arsenic-bronze dagger: Imported Tin → NOT Dendritic Microstructure.
Allows deduction of microstructural characteristics directly from the presence of imported tin.
3
Apply the derived conditional chain to the quantified subset in Premise 3.
Because 'most' Cycladic arsenic-bronze daggers contain imported tin, that majority subset cannot have been cast in an open stone mold and therefore cannot exhibit a dendritic crystalline microstructure. A majority ('most') strictly entails 'at least some'.
Deduces the necessary inference that is logically guaranteed by the intersection of the conditional chain and the quantifier.

Anahtar Kavram

Quantifier Intersection and Conditional Contrapositive Chaining
Tahmini Süre:2m 0s
Soru 124Soru →

Economist: An emerging technology sector can achieve sustained capital investment only if regulatory agencies establish transparent intellectual property protections and enforce strict antitrust guidelines. Recent legislation in Valdoria has successfully established fully transparent patent protections and mandated comprehensive antitrust enforcement across its domestic software industry. Thus, Valdoria's software industry is now assured of securing sustained capital investment in the coming fiscal cycle.

Which of the following most accurately describes a flaw in the economist's reasoning?

Cevabı ve açıklamayı göster

Cevap: infers that a set of conditions that is required for an outcome is also sufficient to guarantee that outcome

Cevap

The argument is flawed because it infers that a set of conditions required for an outcome is sufficient to guarantee that outcome.
The economist establishes that intellectual property protections and antitrust enforcement are necessary conditions ('only if') for sustained capital investment. In the conclusion, the economist asserts that because these prerequisites have been fulfilled, sustained investment is assured. This erroneously equates a necessary requirement with a sufficient guarantee.

Adım Adım Çözüm

1
Identify the conclusion and premises in the stimulus.
Premise 1: Sustained investment requires transparent IP protections and strict antitrust enforcement (Investment → Protections & Enforcement). Premise 2: Valdoria has established transparent protections and strict antitrust enforcement. Conclusion: Valdoria's software industry is assured of securing sustained capital investment.
Separating the conditional rule from the factual premise isolates the logical bridge.
2
Evaluate the conditional relationship established by the economist.
The indicator 'only if' introduces a necessary condition. Satisfying a necessary condition satisfies a prerequisite, but it does not guarantee that the sufficient condition (sustained investment) will occur.
Necessary conditions are mandatory requirements, not affirmative guarantees.
3
Match the identified flaw with the correct answer description.
The argument commits a classic conditional error by treating necessary conditions as sufficient to guarantee the result.
The precise description of confusing necessity and sufficiency accurately describes the reasoning vulnerability.

Anahtar Kavram

Confusing Necessary and Sufficient Conditions
Tahmini Süre:1m 45s
Soru 125Soru →

Urban Planner: Whenever a metropolitan transit district achieves an on-time rail reliability rate exceeding 90 percent, private vehicle congestion on surrounding arterial highways declines significantly during peak commuting hours. Over the past twelve months, private vehicle congestion on the arterial highways surrounding Central County declined significantly during peak commuting hours. Thus, Central County's transit district must have achieved an on-time rail reliability rate exceeding 90 percent over the past twelve months.

The reasoning in the urban planner's argument is most vulnerable to criticism on the grounds that the argument

Cevabı ve açıklamayı göster

Cevap: infers that a condition is required to achieve a particular outcome merely from the claim that the condition is sufficient to produce that outcome

Cevap

The argument's flaw is that it infers that a condition is required to achieve a particular outcome merely from the claim that the condition is sufficient to produce that outcome.
The argument assumes that achieving over 90 percent rail reliability is the only possible cause of significant congestion reduction. While the premise guarantees that high rail reliability will reduce congestion (sufficient condition), it does not establish that high rail reliability is necessary to reduce congestion. Thus, concluding that high rail reliability must have occurred because congestion declined is a mistaken reversal.

Adım Adım Çözüm

1
Deconstruct the argument into its constituent premises and conclusion.
Premise 1 establishes a conditional rule: If rail reliability exceeds 90 percent, then arterial highway congestion declines significantly. Premise 2 states the factual condition: Arterial highway congestion declined significantly in Central County. Conclusion claims: Central County's rail reliability must have exceeded 90 percent.
Accurately identifying the formal logical relationships in the stimulus is necessary to isolate the structural flaw.
2
Analyze the validity of the conditional inference.
The argument observes that the necessary consequence of the conditional relationship (reduced congestion) has occurred and mistakenly concludes that the sufficient condition (rail reliability exceeding 90 percent) must also have occurred.
This is a classic conditional fallacy known as affirming the consequent or mistaken reversal.
3
Match the identified flaw with the correct abstract description among the choices.
The correct description states that the author treats a condition that is merely sufficient for producing an outcome as if it were necessary (required) for that outcome.
Other factors (such as remote work adoption, fuel price increases, or road expansions) could have caused congestion to drop even if rail reliability remained below 90 percent.

Anahtar Kavram

Conditional Reversal (Affirming the Consequent)
Soru 126Soru →

Geologist: Subglacial volcanic calderas beneath the West Antarctic Ice Sheet are capped by dense ice shelves that exert immense hydrostatic pressure, which generally suppresses explosive eruptions. However, geological sediment cores from the mid-Holocene reveal periodic, catastrophic explosive eruptions from these subglacial vents that coincided precisely with brief intervals of regional ice sheet thinning. Because the reduction in ice volume during these intervals substantially reduced hydrostatic confining pressure, this rapid unloading must have been what triggered the sudden shift to explosive volcanism.

Which one of the following is an assumption on which the geologist's argument depends?

Cevabı ve açıklamayı göster

Cevap: The rapid thinning of the regional ice sheet during the mid-Holocene intervals was not primarily caused by geothermal heat emitted by the subglacial volcanoes prior to their eruptions.

Cevap

The argument depends on the assumption that the rapid thinning of the regional ice sheet was not primarily caused by geothermal heat emitted by the subglacial volcanoes prior to their eruptions.
The author concludes that regional ice thinning caused the shift to explosive eruptions based on a temporal correlation between the two phenomena. For ice unloading to be the initiating trigger, the thinning must not have been merely a byproduct or consequence of the volcanic eruption sequence already occurring. Negating the statement that the thinning was not caused by geothermal heat from the volcanoes means that pre-eruptive volcanic heating melted the ice, rendering the thinning an effect rather than the trigger. Because negating this statement collapses the causal argument, it is an indispensable assumption.

Adım Adım Çözüm

1
Deconstruct the argument into its core premises and conclusion.
Premise: Subglacial ice exerts hydrostatic pressure that suppresses explosive eruptions. Premise: Mid-Holocene core data show explosive eruptions coincided with brief intervals of ice sheet thinning. Premise: Thinning reduces hydrostatic pressure. Conclusion: The reduction in pressure (unloading) triggered the shift to explosive volcanism.
Identifying the exact structural relationship between evidence and the author's causal claim is necessary to spot unstated gaps.
2
Identify potential alternative causal explanations or reverse causality gaps.
The author infers that ice thinning caused the volcanic eruptions simply because they coincided. A fatal vulnerability is reverse causality: if the volcano itself melted the ice before erupting, thinning was an effect rather than the cause.
Necessary assumptions in causal arguments frequently rule out reverse causation or confounding third variables.
3
Apply the Negation Test to the candidate assumption.
Negating the statement yields: 'The rapid thinning was primarily caused by geothermal heat emitted by the subglacial volcanoes prior to their eruptions.' If this is true, the volcanic activity was already underway and caused the thinning, destroying the claim that ice unloading triggered the eruptions.
A true necessary assumption, when logically negated, must completely shatter the validity of the conclusion.

Anahtar Kavram

Necessary Assumption (Defender Archetype / Ruling Out Reverse Causation)

Alternatif Yöntem

Apply the Negation Technique: Negate each choice and test whether the argument's conclusion becomes logically impossible. The statement that shatters the argument upon negation is the necessary assumption.
Tahmini Süre:1m 30s
Soru 127Soru →

Ecologist: Subterranean mycorrhizal fungal networks can transport carbon and defensive biochemical compounds between established canopy trees and developing understory saplings. A forestry study monitored Douglas fir saplings planted within five meters of mature birch trees and compared them to saplings planted in open, cleared plots without neighboring trees. The saplings planted near birch trees grew thirty percent faster and exhibited significantly lower rates of foliar blight. The researchers concluded that subterranean nutrient and defense transfers through shared fungal networks from the birch trees directly account for the improved growth and blight resistance of these saplings.

Which of the following statements, if true, most seriously undermine the researchers' conclusion? (Select all that apply.)

Geçerli olan tümünü seçin

Cevabı ve açıklamayı göster

Cevap: Douglas fir saplings whose root zones were isolated from nearby birch trees by subterranean impermeable mesh barriers that prevent fungal connections exhibited the same enhanced growth rates and blight resistance as connected saplings.; The cleared plots used in the study had undergone heavy mechanical scraping that severely compacted the subsoil and stripped topsoil moisture, whereas the soil surrounding the mature birch trees remained loose and hydrated.

Cevap

The statements establishing that saplings isolated by subterranean mesh barriers still experience the same gains and that the cleared comparison plots suffered from severe soil compaction and degradation together undermine the conclusion.
The conclusion asserts a direct causal relationship: shared underground fungal networks transfer nutrients and signals, causing improved sapling growth and disease resistance. The statement showing that saplings separated by physical mesh barriers still exhibit identical benefits severs the causal mechanism by showing the effect occurs in the absence of the proposed cause. Additionally, the statement detailing severe soil compaction and degradation in the cleared plots provides an alternative explanation for the performance gap between the two test groups, undermining the claim that the birch trees were responsible.

Adım Adım Çözüm

1
Isolate the argument's premises and main conclusion.
Premises establish that birch trees and fir saplings can share fungal networks, and saplings planted near birch trees grew faster and suffered less blight than saplings in cleared plots. Conclusion claims that underground nutrient and defense transfers through fungal networks directly cause these improvements.
Weaken questions require identifying the specific gap between the observed correlation in the premises and the causal claim in the conclusion.
2
Identify unstated assumptions and vulnerabilities in the causal inference.
The author assumes that the fungal network is the causal agent rather than aboveground microclimate factors (e.g., canopy shade), and that the cleared plots were otherwise identical in growing conditions to the soil near the birch trees.
Causal conclusions in observational field studies are vulnerable to confounding baseline differences and alternative causal pathways.
3
Evaluate each answer choice to identify those that break the causal link or introduce plausible alternative explanations.
The option showing identical benefits when fungal connections are physically blocked removes the proposed cause while the effect remains. The option describing degraded soil in the cleared plots introduces a confounding factor that accounts for the disparity.
Both findings directly invalidate the attribution of the effect to shared mycorrhizal transfers.

Anahtar Kavram

Evaluating Causal Arguments and Confounding Variables
Tahmini Süre:2m 15s
Soru 128Soru →

Ethologist: Scrub jays cache food for winter consumption and frequently re-cache their food stores if competing birds are present during the initial caching. In a controlled experiment, jays cached food either in complete isolation or while a competitor watched from behind a transparent barrier. The jays re-cached their food significantly more often when observed through the barrier than when caching in isolation. Therefore, this re-caching behavior is driven by the jays' cognitive assessment of a competitor's visual perspective.

Which of the following are unstated assumptions on which the ethologist's argument depends? (Select all that apply.)

Geçerli olan tümünü seçin

Cevabı ve açıklamayı göster

Cevap: The elevated re-caching frequency in the presence of a competitor was not merely a generalized physiological stress response triggered by seeing another bird.; The scrub jays would not exhibit an identical increase in re-caching frequency if the barrier were completely opaque and blocked the competitor's line of sight.

Cevap

The argument strictly depends on the assumptions that the increased re-caching was not simply a non-cognitive stress response to the sight of another bird, and that jays would not show the exact same re-caching increase if the competitor's line of sight were completely blocked by an opaque barrier.
The conclusion claims that the re-caching behavior is specifically driven by the jays' cognitive assessment of another bird's visual perspective. For this causal cognitive claim to stand, the author must assume both that a non-cognitive alternative explanation (such as generalized physiological stress caused by the mere visual presence of another bird) is not the sole cause, and that the competitor's actual line of sight is essential to the effect (meaning an opaque barrier blocking the view would not elicit an identical increase). Negating either of these statements completely severs the logical connection between the experimental data and the conclusion.

Adım Adım Çözüm

1
Analyze the stimulus argument structure
Premise: Jays re-cached food more often when observed through a transparent barrier than when in isolation. Conclusion: The behavior is driven by a cognitive assessment of the competitor's visual perspective.
Identifying the explicit premises and conclusion reveals the gap between the experimental observation (difference in behavior) and the cognitive claim (visual perspective assessment).
2
Identify unstated gaps and apply the Negation Test to candidate assumptions
Negating the statement ruling out a non-cognitive stress response shows that stress alone could account for the result. Negating the statement regarding an opaque barrier shows that if line of sight does not matter, the behavior cannot be driven by visual perspective.
A necessary assumption must fatally undermine the conclusion when logically negated.
3
Evaluate distractors for common logical fallacies
The remaining choices either state an unnecessarily broad sufficient principle, impose an extreme standard of certainty, or address out-of-scope cache loss rates.
Necessary assumptions must be strictly required, avoiding extreme qualifiers or broader-than-necessary scope.

Anahtar Kavram

Necessary Assumption (Supporter and Defender models with Negation Test)
Tahmini Süre:1m 30s
Soru 129Soru →

Marine geochemists and oceanographers surveying benthic hydrothermal fields have established the following facts regarding deep-sea vent systems:

• Any hydrothermal site that hosts hyperthermophilic methanogen colonies exhibits sub-seafloor serpentinization.
• No site exhibiting sub-seafloor serpentinization possesses basalt crust younger than one million years.
• Every hydrothermal site possessing basalt crust of at least one million years is situated along an ultra-slow spreading ridge.
• Some hydrothermal sites situated along an ultra-slow spreading ridge generate diffuse, low-temperature venting rather than focused chimney discharge.
• Any hydrothermal site that generates diffuse, low-temperature venting is incapable of sustaining predatory siphonophore populations.

Which of the following statements must be true based on the oceanographers' findings? Select all that apply.

Geçerli olan tümünü seçin

Cevabı ve açıklamayı göster

Cevap: Any hydrothermal site that hosts hyperthermophilic methanogen colonies is situated along an ultra-slow spreading ridge.; At least some hydrothermal sites situated along an ultra-slow spreading ridge are incapable of sustaining predatory siphonophore populations.

Cevap

The statements that must be true are the one establishing that any site hosting hyperthermophilic methanogen colonies is on an ultra-slow spreading ridge, and the one establishing that at least some sites along an ultra-slow spreading ridge cannot sustain predatory siphonophores.
The first valid statement directly follows from transitive conditional chaining: Methanogen colonies →\rightarrow Serpentinization →\rightarrow Basalt crust ≥1\ge 1 million years →\rightarrow Ultra-slow spreading ridge. The second valid statement follows from combining the existential premise (some ultra-slow ridge sites have diffuse venting) with the universal conditional rule (diffuse venting →\rightarrow cannot sustain siphonophores), which strictly proves that some ultra-slow ridge sites cannot sustain siphonophores.

Adım Adım Çözüm

1
Formalize the universal conditional statements from the stimulus into symbolic chains.
Methanogen colonies imply Serpentinization; Serpentinization implies Basalt crust ≥1\ge 1 million years; Basalt crust ≥1\ge 1 million years implies Ultra-slow spreading ridge. Diffuse venting implies No siphonophores.
Establishing explicit conditional linkages allows for valid chain deductions and contrapositives.
2
Synthesize the conditional chain from methanogen presence to ridge location.
Methanogen →\rightarrow Serpentinization →\rightarrow Crust ≥1\ge 1 million years →\rightarrow Ultra-slow ridge. Therefore, Methanogen →\rightarrow Ultra-slow ridge.
Transitivity of conditional relationships guarantees that any site hosting methanogens must be on an ultra-slow ridge.
3
Combine the existential quantifier statement with the dependent conditional rule.
There exist ultra-slow ridge sites with diffuse venting, and all diffuse venting sites lack siphonophores. Thus, some ultra-slow ridge sites cannot sustain siphonophores.
An existential statement combined with a universal rule governing the subgroup strictly proves an existential conclusion about that subgroup.
4
Evaluate and eliminate all invalid inferences.
Reversals, invalid negations, and unwarranted universal generalizations are discarded.
Only deductively guaranteed statements satisfy the standard for must be true questions.

Anahtar Kavram

Conditional Chaining and Quantifier Synthesis in Formal Deductive Logic
Tahmini Süre:2m 0s
Soru 130Soru →

Each of the following arguments exhibits a distinct reasoning vulnerability. Match each flawed argument with the statement that most accurately describes its primary logical flaw.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Journalist: Our magazine has an editorial obligation to publish material that serves the public interest. Because recent reader surveys demonstrate that the general public is intensely interested in the private romantic lives of celebrities, publishing our planned series of celebrity gossip articles directly fulfills our editorial obligation.
Museum Administrator: To eliminate our operating deficit, we must either double the general admission fee or cancel our public arts education program. Because doubling the admission fee would alienate our core visitors, we must cancel the education program.
Civil Advocate: The lead structural engineer presented comprehensive stress-test data indicating that the new municipal bridge is completely safe for heavy transit. However, because that engineer's firm will receive a sizable financial bonus if the bridge opens ahead of schedule, the bridge cannot be safe.
Policy Analyst: Dr. Vance, a Nobel laureate in theoretical condensed matter physics, recently argued that the city's proposed commercial property tax reform will inevitably trigger retail vacancies. Given Dr. Vance's extraordinary academic distinction, the city council should reject the proposed tax reform.

Eşleşmeler

Cevabı ve açıklamayı göster

Cevap

The journalist's argument matches the description of conflating curiosity with public welfare; the museum administrator's argument matches the assumption that only two exclusive courses of action exist; the civil advocate's argument matches rejecting a claim based on the speaker's financial motives; and the policy analyst's argument matches relying on an authority outside their field of expertise.
Each argument contains a hallmark logical fallacy that matches precisely one abstract description: shifting word definitions matches the equivocation description; presenting an exhaustive two-option scenario matches the false dilemma description; dismissing empirical data because of compensation bonuses matches the motive attack description; and using physics prestige to validate tax claims matches the unqualified authority description.

Adım Adım Çözüm

1
Isolate the conclusion and premises of each argument in the left column.
Identified four independent flawed arguments: semantic shift in the journalism argument, restricted alternatives in the museum argument, motive attack in the engineering argument, and out-of-field authority in the physics/tax argument.
Accurately identifying the reasoning gap between premise and conclusion is necessary to match each argument to its abstract description.
2
Map each argument's specific vulnerability to standard formal flaw archetypes.
The arguments represent equivocation (public interest), false dichotomy (two budget options), ad hominem/motive (bonus incentive), and appeal to unqualified authority (physicist on tax policy).
Abstract descriptions on the LSAT translate concrete argumentative defects into generalized logical principles.
3
Pair each argument with its exact corresponding abstract formulation.
All four pairs matched unequivocally with no overlap or ambiguity.
Ensures that every pair is uniquely and correctly aligned based on structural logic.

Anahtar Kavram

Flaw in the Reasoning: Identifying Fallacies and Structural Flaws (Equivocation, False Dilemma, Ad Hominem Motive Attack, and Inappropriate Authority)
Tahmini Süre:1m 30s
Soru 131Soru →

Archival conservators analyzing the preservation of historical documents have established the following facts regarding iron gall ink manuscripts:

• Any manuscript written with iron gall ink that is kept in an environment where relative humidity exceeds 65 percent undergoes acid hydrolysis, which accelerates cellulose breakdown.
• If cellulose breakdown is accelerated in a manuscript, its paper substrate becomes brittle unless the manuscript has been treated with a calcium phytate deacidification wash.
• Every manuscript in the Morrison Collection that exhibits paper substrate brittleness also exhibits significant copper ion migration into its surrounding binding.
• None of the manuscripts in the Morrison Collection have ever received a calcium phytate deacidification wash.

If the statements above are true, which one of the following must also be true?

Cevabı ve açıklamayı göster

Cevap: Any manuscript in the Morrison Collection written with iron gall ink that is kept in an environment where relative humidity exceeds 65 percent exhibits significant copper ion migration into its surrounding binding.

Cevap

Any manuscript in the Morrison Collection written with iron gall ink that is kept in an environment where relative humidity exceeds 65 percent exhibits significant copper ion migration into its surrounding binding.
The correct statement is logically guaranteed by linking the stimulus premises: an iron gall manuscript kept above 65 percent relative humidity experiences accelerated cellulose breakdown; since Morrison Collection items lack calcium phytate washes, this breakdown ensures substrate brittleness, which in turn guarantees copper ion migration into the binding.

Adım Adım Çözüm

1
Formalize the conditional premises from the stimulus
1. Iron Gall + RH > 65% → Acid Hydrolysis → Accelerated Cellulose Breakdown
2. Accelerated Cellulose Breakdown + No Calcium Phytate Wash → Brittle Substrate
3. Morrison Collection + Brittle Substrate → Copper Ion Migration
4. Morrison Collection → No Calcium Phytate Wash
Establishing explicit conditional representations isolates the logical links between properties.
2
Connect the premises applicable to manuscripts in the Morrison Collection
For any Morrison Collection manuscript: Iron Gall + RH > 65% leads to Accelerated Cellulose Breakdown. Because all Morrison manuscripts lack the wash, this breakdown strictly guarantees Brittle Substrate, which in turn strictly guarantees Copper Ion Migration.
Combining the universal collection property with the conditional rules yields an unbroken deductive deduction.
3
Identify the statement that matches this direct deduction
The statement asserting that an iron gall manuscript in the Morrison Collection kept at RH > 65% must exhibit copper ion migration is logically certain.
A valid 'Must Be True' conclusion must follow inevitably without importing outside assumptions.

Anahtar Kavram

Deductive Conditional Chaining
Tahmini Süre:1m 20s
Soru 132Soru →

Marine Biologist: Any coral reef ecosystem that undergoes a rapid recovery following a severe thermal bleaching event must possess high functional herbivore diversity, because herbivorous fish graze down macroalgae that would otherwise outcompete newly settling coral recruits. Recent monitoring surveys confirmed that the Tuvana Atoll reef system has maintained exceptionally high functional herbivore diversity over the past decade. Therefore, following last summer's severe bleaching event, the Tuvana Atoll reef system will undoubtedly achieve a rapid recovery.

The reasoning in the marine biologist's argument is most vulnerable to criticism on the grounds that the argument

Cevabı ve açıklamayı göster

Cevap: treats a condition that is necessary for rapid coral recovery as though it were sufficient to guarantee that recovery

Cevap

Treats a condition that is necessary for rapid coral recovery as though it were sufficient to guarantee that recovery
The premise states that any reef undergoing rapid recovery 'must possess' high functional herbivore diversity, making high diversity a necessary condition for rapid recovery. The author then notes that Tuvana Atoll satisfies this necessary condition and concludes that it will certainly achieve rapid recovery. This is a classic conditional error: it mistakenly assumes that satisfying a necessary condition is sufficient to guarantee the outcome.

Adım Adım Çözüm

1
Analyze the conditional relationship in the opening premise
Rapid recovery requires high functional herbivore diversity (Rapid Recovery → High Herbivore Diversity).
Identifying the formal structure reveals that herbivore diversity is established as a necessary requirement, not a guarantee.
2
Examine the application to the specific subject and conclusion
The argument observes that Tuvana Atoll possesses high herbivore diversity and concludes it must rapidly recover.
This establishes that the author affirms the necessary condition to infer the sufficient condition (mistaken reversal).
3
Match the structural error to the abstract description
The flaw is confusing a necessary condition with a sufficient condition.
Having high diversity is essential, but other factors could prevent recovery, meaning diversity alone is not sufficient.

Anahtar Kavram

Flaw in the Reasoning: Necessary versus Sufficient Condition Confusion (Conditional Reversal)
Tahmini Süre:1m 15s
Soru 133Soru →

Linguist: In a multi-year study of bilingual children, researchers found that those who acquired their second language primarily through unstructured conversational immersion exhibited a significantly higher degree of grammatical flexibility and were more likely to generate novel linguistic structures than those who acquired it through formal classroom instruction. Because formal instruction relies heavily on the rote memorization of rigid syntactic rules, it is evident that such structured educational environments stifle the cognitive creativity naturally associated with language acquisition.

Which one of the following, if true, most seriously weakens the linguist's argument?

Cevabı ve açıklamayı göster

Cevap: Children who demonstrate a lower baseline aptitude for spontaneous linguistic pattern recognition are disproportionately channeled by educators into formal classroom instruction.

Cevap

Children who demonstrate a lower baseline aptitude for spontaneous linguistic pattern recognition are disproportionately channeled by educators into formal classroom instruction.
The linguist makes a massive causal leap from a simple correlation: because children in formal instruction exhibit less creativity, the instruction must be causing that lack of creativity. The correct answer highlights a severe selection bias by demonstrating that children who already lack a natural aptitude for spontaneous linguistic pattern recognition (a core element of the creativity being measured) are disproportionately placed into formal instruction. This provides a compelling alternative explanation for the study's results: the difference in creativity existed before the instruction even began. By providing an alternate cause for the phenomenon, it severs the causal link the linguist attempted to establish.

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1
Identify the main conclusion of the linguist's argument.
The conclusion is that structured educational environments (formal instruction) stifle the cognitive creativity associated with language acquisition.
Accurately targeting the conclusion is required to find the logical gap in a Weaken question.
2
Identify the premises supporting this conclusion.
The primary premise is a correlation: children in formal instruction exhibit less grammatical flexibility and produce fewer novel structures than children in immersion environments.
Understanding the evidence allows you to see how the author makes the leap from premise to conclusion.
3
Analyze the logical gap in the causal reasoning.
The author assumes that the educational environment is the CAUSE of the difference in creativity. The gap is the failure to consider alternative explanations, such as a pre-existing difference between the two groups of children.
Causal arguments based on observational studies are highly vulnerable to selection bias or reverse causality.
4
Evaluate the options to find one that attacks this specific gap.
The correct option reveals that children who already lack a natural aptitude for linguistic pattern recognition are selectively placed into formal instruction.
This alternative explanation accounts for the lower creativity in the formally instructed group without accepting the conclusion that the instruction itself caused the stifling, thereby dismantling the argument.

Anahtar Kavram

Causal Reasoning: Selection Bias and Alternative Explanations
Soru 134Soru →

A municipal library system recently abolished all late fees on overdue books to encourage patrons to return borrowed materials without fear of financial penalty. Following the implementation of this policy, library records indicated that the average duration a borrowed book remained overdue before being returned increased by two weeks. Nevertheless, the total percentage of checked-out books that were permanently lost or never returned at all decreased by more than half. Which of the following, if true, most helps to resolve the apparent discrepancy described above?

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Cevap: Under the previous policy, patrons who accrued substantial late fees frequently kept overdue books indefinitely to avoid penalties, whereas without fines, they eventually returned them after an extended delay.

Cevap

The statement explaining that patrons who previously kept books indefinitely to evade compounding fines now return them after extended delays reconciles both observed trends.
The correct choice successfully bridges both facts: by removing punitive compounding fines, patrons who previously kept books indefinitely to avoid paying large penalties were willing to return them. Because these materials were returned after long periods rather than kept forever, they were no longer counted as permanent losses (explaining the drop in lost books) and their extended return times pulled up the average overdue duration (explaining the increase in average overdue time).

Adım Adım Çözüm

1
Identify the two competing facts in the stimulus.
Fact 1: The average duration overdue books remained out before being returned increased by two weeks. Fact 2: The overall proportion of books permanently lost or never returned dropped by over 50%.
Resolving a paradox requires isolating both sides of the apparent conflict before looking for an explanatory bridge.
2
Formulate the necessary characteristics of a resolving statement.
The correct explanation must provide a mechanism where the very same change allows or causes returned books to take longer on average while simultaneously preventing books from being permanently kept.
An effective resolution cannot deny either fact; it must explain how both outcomes can coexist logically under the new policy.
3
Evaluate the choices to locate the causal bridge.
The explanation showing that long-overdue materials that previously became permanent losses are now returned after significant delays accounts for both a higher average overdue duration among returned items and a sharp drop in permanent losses.
Converting permanent losses into late returns adds high overdue-day values into the average return calculation while directly lowering the unreturned book count.

Anahtar Kavram

Reconciling two seemingly conflicting empirical trends with a single compensatory behavioral mechanism
Tahmini Süre:1m 15s
Soru 135Soru →

Consider the following argument:

Ecologist: In a controlled municipal study, urban green roofs planted exclusively with native sedum species supported a 40 percent higher abundance of native bees than roofs planted with non-native sedum species. Because both groups of roofs had identical total floral surface area and were situated in identical urban microclimates, the higher bee abundance on native sedum roofs must be driven primarily by the superior nutritional quality of native sedum nectar.

Statement: If native bees show no difference in visual attraction to the flower morphology and coloration of native versus non-native sedum species, this finding strengthens the ecologist's conclusion.

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Cevap: True

Cevap

True
The conclusion asserts a specific causal mechanism (nectar nutritional quality) to explain a documented correlation (higher bee abundance on native sedum roofs). The supplementary statement demonstrates that visual floral traits (coloration and morphology) do not differ in their appeal to the bees. By eliminating visual attraction as an alternative explanation for why bees congregate on native sedums, the statement provides meaningful logical reinforcement for the author's nectar-quality hypothesis.

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1
Deconstruct the argument's premises and conclusion
Premise: Native sedum roofs had 40% more native bees despite equal floral surface area and identical microclimates. Conclusion: The preference must be driven primarily by superior nectar nutritional quality.
Identifying the explicit evidence and the exact causal claim reveals the logical gap.
2
Identify the unstated assumption and potential rival causes
The ecologist assumes that non-nutritional factors (such as flower shape, color, or visual attractiveness) do not explain the disparity in bee abundance.
Causal arguments on the LSAT are vulnerable to alternative explanations that could produce the same correlation.
3
Evaluate the impact of the supplementary statement
Confirming that bees do not differ in visual attraction to flower morphology eliminates visual cues as a confounding variable.
Ruling out a plausible alternative explanation directly bolsters the validity of the author's favored causal mechanism.

Anahtar Kavram

Strengthening a causal conclusion by eliminating a plausible alternative explanation
Tahmini Süre:1m 15s
Soru 136Soru →

Argument: To halt the depletion of the native Silverfin fish population, the regional fisheries agency replaced its length-of-season restrictions with a strict, industry-wide annual catch quota. Over the past three years, the total recorded weight of Silverfin caught has not exceeded the new quota limit, yet the overall Silverfin population has declined at a substantially faster rate than before. The agency concludes that the total allowable catch limit was set too high to enable the population to stabilize.

Statement: The argument is significantly weakened by the fact that the industry-wide nature of the quota incentivized fisheries to adopt non-selective drag netting to maximize their catch speed before the total quota is reached, resulting in massive, unrecorded deaths of pre-reproductive Silverfin.

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Cevap: True

Cevap

True. The provided statement accurately identifies a fact that undermines the agency's specific conclusion.
The statement correctly identifies that the new fact undermines the agency's conclusion. The agency concludes that the total catch limit was numerically too high. However, the new fact provides an alternative explanation for the population decline: the 'industry-wide' structure of the quota caused fisheries to change their methods, resulting in unrecorded juvenile deaths. This severs the causal link between the numerical height of the quota limit and the population decline, thereby weakening the argument.

Adım Adım Çözüm

1
Analyze the stimulus to separate the premises from the main conclusion.
Premise: Recorded catch met the new quota, but the population declined faster. Conclusion: The numerical limit of the catch quota was set too high.
Identifying the exact conclusion is necessary to determine what specifically must be weakened.
2
Identify the logical gap or assumption in the agency's reasoning.
The agency assumes that the recorded catch is the only variable affecting the population and that the numerical limit is the primary cause of the continued decline.
Weaken questions require attacking the unstated assumptions bridging the premises and the conclusion.
3
Evaluate the impact of the new fact presented in the statement on the agency's conclusion.
The fact introduces an alternative cause: the structural design of the quota (industry-wide) caused unrecorded juvenile deaths via a new fishing method.
If an alternative cause explains the observed effect (population decline), it weakens the agency's claim that the limit itself was the cause.
4
Determine the final truth value of the statement.
Because the fact successfully introduces an alternative explanation that severs the agency's causal link, the statement that 'the argument is significantly weakened' is True.
This confirms the statement accurately evaluates the logical impact of the new fact.

Anahtar Kavram

Alternative Explanations and Causal Flaws
Soru 137Soru →

Philosopher of Science: To objectively evaluate a scientific theory, a researcher must be able to isolate the theory's predictions from their own pre-existing biases. When a scientific discipline is dominated by a single paradigm, researchers are unconsciously influenced by the paradigm's core assumptions, making it impossible for them to isolate their evaluations from bias. Therefore, to ensure that objective evaluation of theories is possible, a discipline must actively dismantle any dominant paradigm. Clearly, once a dominant paradigm is removed from a discipline, its researchers will be capable of objectively evaluating theories.

The reasoning in the philosopher's argument is most vulnerable to criticism on which of the following grounds?

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Cevap: treats the elimination of a condition that makes a desired outcome impossible as sufficient to guarantee that the outcome is possible

Cevap

The argument treats the elimination of a condition that makes a desired outcome impossible as sufficient to guarantee that the outcome is possible.
The argument establishes that a dominant paradigm makes objective evaluation impossible, meaning the absence of a dominant paradigm is necessary for objective evaluation to be possible. However, the conclusion asserts that simply removing the dominant paradigm guarantees researchers will be capable of objective evaluation. This incorrectly treats a necessary condition (removing the paradigm) as a sufficient condition, overlooking other potential barriers. The correct option accurately describes this by stating the argument treats the elimination of a condition that makes an outcome impossible as sufficient to guarantee that it is possible.

Adım Adım Çözüm

1
Map the logical structure of the given premises.
Objective evaluation requires isolating biases. A dominant paradigm makes isolating biases impossible. Therefore, a dominant paradigm makes objective evaluation impossible.
Understanding the precise conditional relationships is necessary to identify logical gaps.
2
Identify the necessary and sufficient conditions established by the premises.
Because a dominant paradigm guarantees the impossibility of objective evaluation, the absence (or removal) of a dominant paradigm is a necessary condition for objective evaluation to be possible.
This establishes what must be true according to the author's own evidence.
3
Analyze the scope and modality of the conclusion.
The argument concludes that once a dominant paradigm is removed, researchers will definitely be capable of objectively evaluating theories.
Comparing the conclusion to the premises reveals the flaw.
4
Identify the logical flaw.
The author assumes that because removing the paradigm is necessary to make objective evaluation possible, it is sufficient to guarantee that it is possible. The author overlooks other potential barriers to objective evaluation (e.g., funding biases, personal ambitions).
This is a classic necessary vs. sufficient logical fallacy.
5
Match the flaw to the abstract description in the correct option.
The correct option correctly identifies that the argument treats the elimination of a condition that ensures impossibility as sufficient to guarantee possibility.
Flaw questions often use abstract terminology to describe concrete logical errors.

Anahtar Kavram

Identifying Conditional Logic Flaws (Necessary vs. Sufficient)
Tahmini Süre:2m 30s
Soru 138Soru →

Consider the following argument: A municipal commuter rail system reported a 15 percent increase in passenger volume during the three months following the installation of free onboard Wi-Fi. The transit authority concluded that offering the complimentary Wi-Fi service was the primary reason for the surge in commuters.

Statement: The fact that a major parallel highway bridge was closed for emergency repairs during those exact same three months weakens the transit authority's conclusion.

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Cevap: True

Cevap

True: The statement accurately notes that introducing an alternate explanation for the increased ridership weakens the transit authority's causal claim.
The statement is true because the emergency highway closure offers an obvious alternate cause for the commuter surge, directly weakening the author's claim that onboard Wi-Fi was the primary driver.

Adım Adım Çözüm

1
Identify the argument's premises and main conclusion.
Premise: Passenger numbers increased after Wi-Fi was added. Conclusion: Wi-Fi was the primary cause of the increase.
Isolating the causal link is necessary to determine what would undermine the argument.
2
Assess the logical impact of the supplementary statement.
The emergency closure of a major parallel highway provides an independent reason why drivers switched to the train during that exact period.
Providing a viable alternative cause for an observed effect directly weakens a causal conclusion.
3
Evaluate the truth value of the statement.
Because the alternate cause undermines the original causal attribution, the assertion that it weakens the argument is true.
The statement correctly classifies the weakening effect of the new evidence.

Anahtar Kavram

Weakening a causal conclusion by identifying an alternative explanation
Tahmini Süre:45s
Soru 139Soru →

Match each flawed argument excerpt on the left with the logical reasoning flaw it most clearly exhibits on the right.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Every member of the municipal council voted in favor of the transit budget immediately after meeting with union representatives. Therefore, the union representatives must have caused the council members to support the budget.
The lead engineer argues that the bridge design is structurally unsafe. However, because she was recently passed over for a promotion by the transit authority, her assessment can be safely dismissed.
To qualify for the honors scholarship, an applicant must have a grade point average above 3.8. Since Marcus has a 3.9 grade point average, he is guaranteed to receive the honors scholarship.
A survey of fifty patrons exiting a high-end boutique in the financial district found that a majority supported higher tariffs on foreign luxury items. Thus, the general public clearly supports these tariffs.

Eşleşmeler

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Cevap

The argument concerning council voting aligns with inferring causation from temporal sequence; the argument regarding the engineer aligns with attacking personal motives; the argument regarding scholarship qualification aligns with confusing necessary and sufficient conditions; and the argument regarding boutique patrons aligns with generalizing from an unrepresentative sample.
Each pair correctly matches an argument with the precise flaw that undermines its reasoning: confusing temporal sequence with causation, dismissing an argument based on personal motives, treating a necessary condition as sufficient, and drawing a conclusion about a whole population from an unrepresentative sample.

Adım Adım Çözüm

1
Analyze the first argument regarding municipal council voting
The argument concludes that one event caused another solely based on chronological sequence.
Inferring causation strictly from sequential timing is a post hoc fallacy.
2
Analyze the second argument regarding the engineer's safety assessment
The argument rejects a substantive technical claim by citing the speaker's potential employment bias.
Dismissing an argument based on the speaker's personal background or motives is an ad hominem flaw.
3
Analyze the third argument regarding scholarship qualification
The argument assumes satisfying a minimum requirement guarantees the ultimate outcome.
Treating a prerequisite (necessary condition) as a guarantee (sufficient condition) is a formal conditional reasoning error.
4
Analyze the fourth argument regarding luxury import tariffs
The argument uses a survey of shoppers at a single luxury boutique to reach a conclusion about the entire public.
Extrapolating from a narrow, unrepresentative group to the whole population is a sampling error.

Anahtar Kavram

Identifying formal and informal reasoning flaws in logical arguments
Soru 140Soru →

Agricultural Scientist: Vineyards in the Aris Valley that planted crimson clover between vine rows experienced a 40 percent lower incidence of grapevine leafroll virus than vineyards maintaining bare soil. Because crimson clover attracts predatory lady beetles that feed voraciously on mealybugs, which are the sole vectors of leafroll virus, the clover reduces viral infection specifically by suppressing the mealybug population.

Statement: If true, the discovery that vineyards with crimson clover maintained average mealybug densities per vine identical to those in bare-soil vineyards weakens the agricultural scientist's argument.

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Cevap: True

Cevap

True, because evidence showing unchanged mealybug populations directly undermines the author's claim that clover reduces viral disease specifically by suppressing mealybug numbers.
The correct assessment is True because the scientist's conclusion specifically attributes the disease reduction to the suppression of mealybug populations. If clover vineyards had the exact same density of mealybugs as bare-soil vineyards, the reduction in disease transmission must be due to some other factor, thereby directly undermining the scientist's explanatory hypothesis.

Adım Adım Çözüm

1
Identify the argument's premises and main conclusion
Premises: Clover vineyards had 40% less leafroll virus than bare-soil vineyards; clover attracts lady beetles that eat virus-carrying mealybugs. Main conclusion: Clover reduces viral infection specifically by suppressing mealybug populations.
Weaken questions require isolating the exact claim the author attempts to prove.
2
Analyze the causal mechanism connecting the premises to the conclusion
The author assumes that attracting lady beetles actually succeeded in reducing the mealybug population, which in turn reduced disease transmission.
Attacking the proposed intermediary mechanism is a standard way to weaken a causal argument.
3
Evaluate the impact of the supplementary statement
If mealybug densities were identical in both groups of vineyards, lady beetle predation did not decrease vector density, falsifying the claimed mechanism of action.
Showing that the hypothesized mechanism did not occur undermines the specific conclusion drawn.

Anahtar Kavram

Undermining a causal conclusion by providing evidence that the proposed causal mechanism did not occur.
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Logical Reasoning Alıştırma Soruları — LSAT — Sayfa 7 | Examkin