Examkin

Logical Reasoning

666 soru

Tüm türler666Çoktan seçmeli343Çoklu seçim54Doğru / Yanlış70Eşleştirme166Sıralama18Boşluk doldurma10Kısa cevap5
Soru 321Soru →

Match each of the following arguments with the underlying unstated assumption that is strictly required for its conclusion to be logically justified.

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Öğeler

Cognitive Scientist: Monolingual infants lose sensitivity to non-native phonetic contrasts by their first birthday, whereas bilingual infants maintain sensitivity to contrasts in both languages beyond twelve months. Therefore, early multilingual speech exposure directly prevents the neural pruning of auditory discrimination pathways.
Agronomist: Coffee farms transitioning from open-field monocultures to canopy-shaded agroforestry systems decreased synthetic nitrogen fertilizer applications by forty percent over five years with no drop in crop yield. Thus, the shade trees' fallen foliage and root systems supply the nitrogen needed to replace the synthetic fertilizer.
Dendrochronologist: Subpolar larch tree rings from the mid-sixth century exhibit three consecutive years of exceptionally narrow, low-density wood cells—a structural deformity observed in living larches exclusively during severe summer temperature drops. Hence, a major climate-cooling event occurred during those three years.

Eşleşmeler

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Cevap

The cognitive scientist's argument matches the assumption regarding the absence of generalized auditory developmental delays; the agronomist's argument matches the assumption regarding soil moisture and nutrient absorption efficiency; and the dendrochronologist's argument matches the assumption ruling out non-climatic insect defoliation disturbances.
Each correct pairing links an argument to a defender assumption that eliminates an unaddressed alternative explanation. For the cognitive science argument, ruling out a developmental maturation lag ensures the retained sensitivity is an effect of language exposure. For the agricultural argument, ruling out moisture-enhanced uptake of residual nutrients ensures the trees themselves are providing the nutrient substitute. For the dendrochronology argument, ruling out insect infestations ensures that ring deformities can be uniquely attributed to low temperatures.

Adım Adım Çözüm

1
Analyze each argument's premise-to-conclusion logical leap
Identify the unstated defender assumptions needed to rule out alternative explanations in each domain (neural maturation delays, moisture-driven nutrient uptake efficiency, and biological defoliation).
A necessary assumption must be essential to the argument such that its falsity destroys the reasoning.
2
Apply the Negation Test to candidate assumptions
Confirm that negating each matched assumption entirely invalidates its corresponding conclusion.
If an argument can still hold when a statement is negated, that statement is not a necessary assumption.
3
Match each argument uniquely to its requisite assumption
Pair Argument 1 with Assumption 2, Argument 2 with Assumption 3, and Argument 3 with Assumption 1.
Each domain-specific logical gap maps strictly to its targeted defender assumption.

Anahtar Kavram

Necessary Assumption (Defender Assumption & Negation Test)
Tahmini Süre:1m 30s
Soru 322Soru →

Literary Historian: A newly discovered manuscript attributed to the seventeenth-century essayist Clara Vance contains descriptions of a rare solar eclipse that occurred in the autumn of 1682. Historical records confirm that Vance died in the spring of 1680. Therefore, this manuscript could not have been written by Vance.

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

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Cevap: The descriptions of the 1682 solar eclipse were not added to the manuscript by someone else after Vance's death.

Cevap

The argument depends on the assumption that the descriptions of the 1682 solar eclipse were not added to the manuscript by someone else after Vance's death.
The historian's conclusion that Vance could not have written the manuscript relies entirely on the premise that the text describes an event from 1682, two years after Vance's death in 1680. For this timeline discrepancy to rule Vance out as the author, the eclipse references must reflect the original composition rather than posthumous alterations. If those descriptions were inserted into Vance's draft by someone else after 1680, the core manuscript could still be her authentic work. Thus, negating this assumption destroys the conclusion, confirming it is strictly necessary.

Adım Adım Çözüm

1
Identify the premises and conclusion of the argument.
Premises: The manuscript contains descriptions of an eclipse in autumn 1682; Vance died in spring 1680. Conclusion: The manuscript could not have been written by Vance.
Understanding the structure isolates the logical gap between the evidence and the claim.
2
Identify potential objections or alternative explanations that would allow Vance to be the author.
Vance could have written the original manuscript if the passage referencing the 1682 eclipse was inserted into the document later by an editor or another writer.
Necessary assumptions often defend the conclusion by ruling out plausible ways the conclusion could fail despite true premises.
3
Apply the Negation Test to verify the required assumption.
Negating the statement yields: 'The descriptions were added to the manuscript by someone else after Vance's death.' This destroys the conclusion that Vance could not have written the manuscript.
A necessary assumption must fatally undermine the conclusion when logically negated.

Anahtar Kavram

Necessary Assumption (Defender Assumption)
Tahmini Süre:1m 0s
Soru 323Soru →

Consider the following statements:

Under the Interplanetary Spaceflight Accord, every commercial vehicle operating in low Earth orbit that carries pressurized volatile propellants must either be equipped with an autonomous passivation valve or maintain a continuous active telemetry link with the orbital safety registry. Any orbital vehicle equipped with an autonomous passivation valve must undergo thermal-vacuum qualification prior to launch. Furthermore, no vehicle that undergoes thermal-vacuum qualification is permitted to utilize non-radiation-hardened microcontrollers in its flight control system. The Aethelgard-4 is a commercial vehicle operating in low Earth orbit that carries pressurized volatile propellants and utilizes a non-radiation-hardened microcontroller in its flight control system.

Based strictly on the information provided, evaluate the truth value of the following statement:
The Aethelgard-4 maintains a continuous active telemetry link with the orbital safety registry.

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Cevap: True

Cevap

True — Based strictly on the premises, the Aethelgard-4 must maintain a continuous active telemetry link with the orbital safety registry.
The statement must be true because the Aethelgard-4 meets the criteria for low Earth orbit operations with volatile propellants, requiring either a passivation valve or continuous telemetry. Since its flight computer uses non-radiation-hardened components, it cannot have undergone thermal-vacuum qualification, ruling out the passivation valve. Consequently, the active telemetry link is logically required.

Adım Adım Çözüm

1
Extract and formalize the conditional rules from the regulatory premises.
Rule 1: (Low Earth Orbit and Pressurized Volatile Propellants) -> (Autonomous Passivation Valve OR Continuous Active Telemetry Link). Rule 2: Autonomous Passivation Valve -> Thermal-Vacuum Qualification. Rule 3: Thermal-Vacuum Qualification -> NOT Non-Radiation-Hardened Microcontrollers.
Translating the prose into structured conditional statements establishes the formal relationships between technical requirements.
2
Apply contraposition to the conditional chain using the factual characteristics of the Aethelgard-4.
Non-Radiation-Hardened Microcontroller -> NOT Thermal-Vacuum Qualification -> NOT Autonomous Passivation Valve.
Because the Aethelgard-4 is known to utilize non-radiation-hardened microcontrollers, following the contrapositives of Rules 3 and 2 eliminates the possibility that it has an autonomous passivation valve.
3
Apply disjunctive syllogism to the first conditional rule.
Since the Aethelgard-4 triggers Rule 1 and cannot satisfy the disjunction via an autonomous passivation valve, it must satisfy the remaining disjunct: maintaining a continuous active telemetry link.
When a necessary disjunctive requirement has one disjunct proven false, the other disjunct must be true.

Anahtar Kavram

Deductive Conditional Chaining, Contraposition, and Disjunctive Syllogism
Tahmini Süre:2m 0s
Soru 324Soru →

Each of the following arguments contains an inferential gap between its stated premise and its conclusion. Match each argument with the assumption that, if assumed, is logically sufficient to guarantee that the conclusion follows deductively.

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Öğeler

Premise: Any company that implements closed-loop water recycling reduces total factory waste.
Conclusion: Hydrolix Enterprises will experience increased long-term profitability.
Premise: Every municipality that builds protected cycling networks experiences a marked decrease in urban traffic congestion.
Conclusion: The city of Oakhaven will receive the National Clean Transit Award.
Premise: All medical research laboratories that use double-blind verification protocols eliminate reporting bias in clinical trials.
Conclusion: Vitasyn Laboratories will secure immediate regulatory authorization.

Eşleşmeler

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Cevap

Each argument is matched with the conditional statement linking its explicit intermediate outcome to its specific final conclusion: the Hydrolix argument pairs with the statement that reducing factory waste yields increased long-term profitability; the Oakhaven argument pairs with the statement that decreased traffic congestion earns the National Clean Transit Award; and the Vitasyn argument pairs with the statement that eliminating reporting bias secures regulatory authorization.
For each pairing, the matched assumption provides a universal conditional link where the antecedent matches the outcome from the premise and the consequent matches the exact claim made in the conclusion. When combined with the premise, this creates a valid hypothetical syllogism that deductively validates the conclusion.

Adım Adım Çözüm

1
Identify the premise and conclusion structure for each argument to isolate the unstated link.
Each argument follows a linear conditional chain where Premise establishes [Condition A → Condition B], but Conclusion claims [Entity possessing Condition A → Condition C].
Sufficient assumptions must supply a valid conditional rule [Condition B → Condition C] to connect the existing premise to the novel conclusion term.
2
Match each argument's intermediate result with the corresponding right-side rule providing the exact conclusion term.
Hydrolix's reduced factory waste connects to increased profitability; Oakhaven's decreased traffic congestion connects to the Clean Transit Award; Vitasyn's elimination of reporting bias connects to regulatory authorization.
Plugging in the premise plus the sufficient bridge fully forces the conclusion to be true in each case.

Anahtar Kavram

Sufficient Assumption Conditional Bridging
Tahmini Süre:1m 0s
Soru 325Soru →

Archaeologist: Obsidian tools discovered at the inland Neolithic settlement of Karasura match the unique geochemical composition of deposits from the volcanic island of Milos, situated hundreds of kilometers away across open water. Since no watercraft from this era have been recovered in the regional archaeological record, several researchers maintain that the tools arrived via roundabout overland trading routes. However, traversing the rugged coastal mountain ranges on foot would have been vastly more perilous and resource-intensive than open-water seafaring. Therefore, the discovery of these tools at Karasura proves that the settlement's inhabitants possessed indigenous seafaring capabilities far earlier than conventional chronologies suggest.

Which of the following statements, if true, each weaken the archaeologist's argument? (Select all that apply)

Geçerli olan tümünü seçin

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Cevap: Geochemical analyses of obsidian artifacts from several contemporary coastal island settlements reveal that their seafaring residents regularly acquired Milian obsidian and exchanged finished tools with mainland populations.; During the Neolithic period, an established network of regional down-the-line exchange allowed valuable raw materials to pass between adjacent neighboring communities over short distances without any single community traveling long distances or braving mountain terrain.

Cevap

The statements showing that maritime islanders traded the tools to mainland communities and that down-the-line regional exchange moved goods across short distances without long journeys each weaken the argument.
The author concludes that Karasura's inhabitants must have independently developed seafaring capabilities based solely on the presence of island obsidian and the difficulty of overland travel. The statement describing intermediary coastal islanders who acquired the obsidian and traded it with mainland groups directly provides an alternative explanation that relieves Karasura's inhabitants of the need to sail. Similarly, the statement explaining down-the-line exchange shows that goods could move incrementally across adjacent communities without requiring any single community to navigate hazardous mountains or sail open seas.

Adım Adım Çözüm

1
Identify the argument's premises and main conclusion
Premises establish that Milian obsidian was found at Karasura, no regional Neolithic boats have been found, and traversing overland mountains was far harder than seafaring. Main conclusion: The discovery proves Karasura's inhabitants possessed indigenous seafaring capabilities earlier than assumed.
Deconstructing the argument isolates the author's leap from the presence of island obsidian to the claim that the settlement's own inhabitants sailed to retrieve it.
2
Expose the unstated assumptions and false dilemma
The author assumes a false dilemma: either Karasura's people endured grueling overland treks or they independently built boats and sailed. This overlooks intermediary trade networks and third-party maritime groups.
Weakening an argument on the LSAT typically involves introducing alternative explanations that break the necessary link between the evidence and the conclusion.
3
Select the statements that provide viable alternative mechanisms
The statement showing intermediary island seafarers traded finished tools and the statement showing short-distance down-the-line land trade each explain the presence of obsidian without requiring Karasura's inhabitants to have seafaring technology.
Both statements independently undermine the conclusion that Karasura developed indigenous maritime capabilities.

Anahtar Kavram

Identifying alternative explanations and exposing false dilemmas in explanatory causal arguments
Soru 326Soru →

Archaeologist: Excavations at the Bronze Age settlement of Tell el-Marwa uncovered numerous ceramic vessels lined with beeswax. Because beeswax was widely used across antiquity as a waterproofing sealant for storing wine and olive oil, and because microscopic residue analysis inside these specific jars lacked lipid signatures characteristic of olive oil, the vessels must have been used almost exclusively for the storage and trade of fermented grape wine.

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

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Cevap: In the region surrounding Tell el-Marwa, beeswax was routinely applied to seal jars containing dry grains and legumes to protect them from ambient humidity.

Cevap

The argument is most seriously weakened by evidence that beeswax was routinely applied to seal jars containing dry grains and legumes to protect them from ambient humidity.
The author concludes that the jars were used almost exclusively for fermented grape wine simply because olive oil residues were absent and beeswax was known to be used for wine and olive oil. This reasoning commits a false dilemma by presuming no other goods were stored in beeswax-lined containers. The correct option directly exposes this flaw by showing that beeswax was routinely used to seal dry grains and legumes against humidity, offering an alternative use that fully explains the physical evidence without supporting the wine conclusion.

Adım Adım Çözüm

1
Identify the premises and conclusion of the argument.
Premises: The jars were lined with beeswax; beeswax was used to waterproof jars for wine and olive oil; the jars lacked olive oil lipid signatures. Main Conclusion: The jars must have been used almost exclusively for storing and trading fermented grape wine.
Deconstructing the argument structure allows identification of the underlying assumptions linking the evidence to the claim.
2
Identify the logical flaw and unstated assumption.
The author assumes a false dichotomy—that because beeswax was used for wine and olive oil, and olive oil is eliminated, wine is the only viable commodity stored in the jars.
To weaken an argument relying on process of elimination, one must show that other unconsidered alternatives exist.
3
Evaluate the answer choices to find new information that exploits this gap.
The finding that beeswax was regularly used to waterproof storage jars for dry grains and legumes provides a direct alternative use that explains the presence of beeswax without implying the presence of wine.
Providing an alternative cause or function severely undermines the exclusivity asserted in the conclusion.

Anahtar Kavram

Alternative Explanations in Causal and Eliminative Arguments
Tahmini Süre:1m 15s
Soru 327Soru →

Nutritionist: Any dietary regimen that successfully reduces systemic inflammation requires the complete elimination of processed sugars. Marcus has completely eliminated processed sugars from his daily meals. Therefore, Marcus's new diet will definitely succeed in reducing systemic inflammation.

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

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Cevap: confuses a condition that is necessary to reduce systemic inflammation with one that is sufficient to do so

Cevap

The argument confuses a condition that is necessary to reduce systemic inflammation with one that is sufficient to do so.
The argument establishes that eliminating processed sugars is a required condition for reducing systemic inflammation ('requires the complete elimination'). It then commits the fallacy of Mistaken Reversal by concluding that because Marcus satisfied this requirement, the reduction in inflammation is guaranteed to occur. The correct choice precisely names this error by pointing out that a necessary condition was treated as a sufficient one.

Adım Adım Çözüm

1
Identify the premises and conclusion in the stimulus
Premise 1: Reducing systemic inflammation requires eliminating processed sugars (Reduction →\rightarrow No Sugar). Premise 2: Marcus eliminated processed sugars (No Sugar). Conclusion: Marcus's diet will reduce systemic inflammation (Reduction).
Deconstructing the argument into formal components isolates the logical link connecting evidence to conclusion.
2
Evaluate the conditional relationship
Eliminating sugar is stated as a requirement (a necessary condition), but the author treats fulfilling that requirement as a guarantee of success (a sufficient condition).
Having a necessary factor does not preclude the existence of other mandatory factors that Marcus might still lack.
3
Match the identified logical error to the options
The statement describing the confusion of a necessary condition with a sufficient condition accurately captures this exact structural error.
Flaw questions require selecting the choice that accurately describes the specific vulnerability in the argument's movement from premise to conclusion.

Anahtar Kavram

Mistaken Reversal (Necessary vs. Sufficient Conditions)
Tahmini Süre:45s
Soru 328Soru →

Historian: Some critics argue that the decline of the ancient city of Veridia was caused solely by prolonged drought. However, archaeological records demonstrate that trade networks collapsed decades before the drought began, and civic infrastructure had already fallen into severe disrepair due to internal political strife. Thus, prolonged drought cannot be considered the sole cause of Veridia's collapse.

Based on the historian's argument, what is the author's main conclusion regarding the collapse of Veridia?

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Cevap: Prolonged drought cannot be considered the sole cause of Veridia's collapse.; Prolonged drought was not the sole cause of Veridia's collapse.; Prolonged drought was not the only cause of Veridia's collapse.; Drought was not the sole cause of Veridia's collapse.; Drought was not the only cause of Veridia's collapse.; Prolonged drought is not the sole cause of the collapse of Veridia.

Cevap

Prolonged drought cannot be considered the sole cause of Veridia's collapse.
The author introduces the critics' position (that drought alone caused the collapse), provides historical premises demonstrating earlier contributing factors (trade network collapse and political strife), and deduces the final conclusion signaled by 'Thus'—that prolonged drought cannot be considered the sole cause of Veridia's collapse.

Adım Adım Çözüm

1
Identify the opposing viewpoint introduced in the context.
Some critics claim that prolonged drought was the sole cause of Veridia's decline.
Arguments frequently begin by stating a counter-thesis that the author intends to refute.
2
Analyze the evidence and premises presented by the author.
Trade collapsed decades earlier and civic infrastructure decayed from political strife before the drought occurred.
These factual premises serve to undermine the claim of single-factor causation.
3
Locate the structural conclusion indicator and extract the ultimate claim.
The statement following 'Thus' directly rejects the critics' sole-cause theory: prolonged drought cannot be considered the sole cause of the collapse.
The conclusion indicator 'Thus' signals the overarching deduction supported by all preceding evidence.

Anahtar Kavram

Identifying the Main Conclusion in Logical Reasoning Arguments
Tahmini Süre:45s
Soru 329Soru →

Match each brief argument with the statement that most effectively strengthens its conclusion.

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Öğeler

A study found that employees who participated in morning exercise sessions reported less back pain than non-participants. The wellness director concluded that morning exercise sessions directly reduce back pain.
A survey of 200 science majors found that over 80 percent preferred digital textbooks to printed textbooks. Based on this finding, the campus bookstore concluded that university students in general prefer digital textbooks.
A delivery company plans to replace its gasoline vans with electric vans, concluding that this change will decrease total vehicle operational costs because electricity costs less per mile than gasoline.

Eşleşmeler

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Cevap

The exercise study argument matches the statement ruling out baseline health differences among participants; the textbook survey argument matches the statement confirming sample representativeness across disciplines; and the electric van argument matches the statement ensuring maintenance expenses do not exceed fuel savings.
Each correct pairing provides evidence that directly resolves the central assumption of its matched argument: eliminating selection bias supports causal attribution, confirming sample typicality supports generalization, and bounding auxiliary expenses supports net cost reduction.

Adım Adım Çözüm

1
Analyze the reasoning gap in each argument.
The exercise argument assumes correlation implies causation without ruling out selection bias; the bookstore argument assumes a specific subgroup represents the whole student body; the delivery company argument assumes fuel savings translate to total operational cost reduction without considering other vehicle expenses.
Identifying the unstated assumption or vulnerability in each argument is necessary to determine what information will strengthen it.
2
Evaluate each potential strengthener against the identified gaps.
Eliminating alternative baseline causes strengthens the causal claim; establishing cross-major consistency strengthens the inductive generalization; bounding ancillary maintenance costs strengthens the total expense claim.
A valid strengthener directly addresses and mitigates the specific logical vulnerability of its target argument.
3
Pair each argument with its corresponding strengthening claim.
Each argument is uniquely paired with the evidence that directly substantiates its specific assumption.
Ensures an exact one-to-one logical correspondence between the arguments and supporting statements.

Anahtar Kavram

Strengthen reasoning: Identifying and bridging distinct logical gaps, including eliminating confounding variables in causal arguments, establishing sample representativeness in generalizations, and accounting for net variables in financial arguments.
Soru 330Soru →

The Silver Basin Ecological Reserve applies strict conservation protocols to all newly restored wetland plots:

• Every wetland plot designated as an active waterfowl habitat receives supplemental aeration during the dry season.
• Any wetland plot that receives supplemental aeration during the dry season is planted exclusively with native emergent reeds.
• No wetland plot planted exclusively with native emergent reeds is treated with synthetic nitrogen fertilizers.
• Last year, Plot 7 and Plot 12 were both designated as active waterfowl habitats, whereas Plot 4 was treated with synthetic nitrogen fertilizers.

If the statements above are true, which of the following statements must also be true? (Select all that apply)

Geçerli olan tümünü seçin

Cevabı ve açıklamayı göster

Cevap: Plot 7 was planted exclusively with native emergent reeds.; Plot 4 was not designated as an active waterfowl habitat last year.

Cevap

The statements establishing that Plot 7 was planted exclusively with native emergent reeds and that Plot 4 was not designated as an active waterfowl habitat must both be true.
The stimulus establishes a strict conditional chain: Active Waterfowl Habitat → Supplemental Aeration → Native Emergent Reeds → No Synthetic Nitrogen Fertilizer. Because Plot 7 was designated as an active waterfowl habitat, following the chain forward guarantees that it was planted exclusively with native emergent reeds. Through contrapositive reasoning (Synthetic Nitrogen Fertilizer → No Native Emergent Reeds → No Supplemental Aeration → Not Active Waterfowl Habitat), the fact that Plot 4 received synthetic nitrogen fertilizers guarantees that it was not designated as an active waterfowl habitat.

Adım Adım Çözüm

1
Diagram the conditional chain from the general rules in the stimulus.
Active Waterfowl Habitat → Supplemental Aeration → Native Emergent Reeds → No Synthetic Nitrogen Fertilizer. The contrapositive is: Synthetic Nitrogen Fertilizer → Not Native Emergent Reeds → No Supplemental Aeration → Not Active Waterfowl Habitat.
Establishing the directional conditional logic is necessary to identify valid forward deductions and contrapositives.
2
Apply the specific facts provided for Plot 7 and Plot 4 to the conditional relationships.
Plot 7 satisfies the sufficient condition of being an active waterfowl habitat, which guarantees that it received aeration, was planted with native emergent reeds, and received no synthetic fertilizer. Plot 4 satisfies the condition of receiving synthetic nitrogen fertilizer, which by contrapositive guarantees it was not planted with native reeds, did not receive aeration, and was not an active waterfowl habitat.
Directly testing factual premises against the chain reveals which claims are logically guaranteed.
3
Evaluate the remaining options for logical fallacies.
Claims asserting that non-fertilized plots must receive aeration, that all reed-planted plots must be waterfowl habitats, or that Plot 12 used organic fertilizers are invalid due to conditional reversal, unwarranted extreme scope, and unaddressed information.
Eliminating invalid deductions confirms the exact set of statements that must be true.

Anahtar Kavram

Deductive Conditional Chaining and Contrapositive Inference
Tahmini Süre:1m 30s
Soru 331Soru →

Each of the three arguments below exhibits a distinct flaw in its reasoning. Match each argument with the statement that most accurately identifies its primary logical flaw.

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Öğeler

Councilor Vance argues that the city should invest in light rail transit, but Vance owns stock in a railway engineering company. Therefore, we should reject the light rail proposal.
Either our retail firm adopts an aggressive price-discounting campaign this quarter, or the business will be forced to shut down entirely before the end of the fiscal year.
Journalists have a duty to report on matters that are of public interest. Because the public is deeply interested in the private lives of film actors, newspapers have an obligation to publish those details.

Eşleşmeler

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Cevap

The argument targeting the councilor matches the dismissal based on personal financial motives; the retail argument matches the assumption that only two extreme possibilities exist; and the journalism argument matches the equivocation between public well-being and public curiosity.
Each flawed argument exhibits a direct correspondence to a distinct logical vulnerability: attacking the proponent's financial stake rather than the merits of the proposal constitutes a source argument; presenting only two extreme options while overlooking moderate paths constitutes a false dichotomy; and shifting the definition of a pivotal term across premises and conclusion constitutes equivocation.

Adım Adım Çözüm

1
Analyze the first argument (Councilor Vance)
The premises attack Vance's stock ownership rather than evaluating whether light rail is beneficial for the city.
Identifying the mismatch between the premises (motive attack) and conclusion (substantive rejection) establishes the ad hominem flaw.
2
Analyze the second argument (Retail firm strategy)
The argument artificially limits the options to price-discounting versus immediate closure.
Recognizing an ungrounded binary choice establishes the false dilemma flaw.
3
Analyze the third argument (Public interest journalism)
The term 'public interest' is used in two different senses: ethical civic importance versus popular curiosity.
Tracking the shift in the core term's definition establishes the equivocation flaw.

Anahtar Kavram

Identification of classical informal fallacies (Source Attack, False Dilemma, Equivocation) in logical reasoning stimuli.
Tahmini Süre:1m 0s
Soru 332Soru →

Highcrest Nature Reserve contains several designated wetland habitats. Furthermore, any nature reserve that provides nesting grounds for migratory waterfowl is eligible for regional conservation grants. Therefore, Highcrest Nature Reserve is eligible for regional conservation grants.

The conclusion drawn above follows logically if which one of the following is assumed?

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Cevap: Any nature reserve that contains designated wetland habitats provides nesting grounds for migratory waterfowl.

Cevap

The statement that any nature reserve containing designated wetland habitats provides nesting grounds for migratory waterfowl logically completes the argument.
The correct answer provides the precise universal conditional bridge needed: Designated Wetlands -> Nesting Grounds. Combining this with the fact that Highcrest has designated wetlands leads to the conclusion that Highcrest provides nesting grounds, which in turn triggers the premise guaranteeing eligibility for regional conservation grants.

Adım Adım Çözüm

1
Break down the premises and conclusion into conditional components
Premise 1: Highcrest contains designated wetland habitats. Premise 2: Nesting grounds for migratory waterfowl implies eligibility for regional conservation grants. Conclusion: Highcrest is eligible for regional conservation grants.
Deconstructing the argument isolates the stated facts from the ultimate claim.
2
Identify the missing link in the chain of reasoning
The premises connect Nesting Grounds to Grants, but we only know Highcrest has Wetlands. The missing link is: Designated wetland habitats guarantee nesting grounds for migratory waterfowl.
A sufficient assumption must establish a 100% deductive bridge between the rogue premise term and the sufficient condition of the rule.
3
Select the option that supplies the exact missing conditional statement
Assuming that any nature reserve containing designated wetland habitats provides nesting grounds completes the syllogism: Highcrest -> Wetland -> Nesting Grounds -> Eligible for Grants.
This guarantees the truth of the conclusion with absolute certainty.

Anahtar Kavram

Sufficient Assumption Conditional Bridging
Tahmini Süre:45s
Soru 333Soru →

Paleoclimatologists analyzing polar ice cores have established the following:

• Every polar ice core segment that exhibits an anomalous sulfate spike without an accompanying basaltic cryptotephra deposit was formed during a period of non-explosive effusive volcanism.
• In the Amundsen-Scott ice core, every segment corresponding to the mid-Holocene climatic anomaly contains either a basaltic cryptotephra deposit or a high concentration of micro-meteoritic iridium, but not both.
• No polar ice core segment containing a high concentration of micro-meteoritic iridium was formed during a period of non-explosive effusive volcanism.
• Sample AS-442 is a segment from the Amundsen-Scott ice core that corresponds to the mid-Holocene climatic anomaly and exhibits an anomalous sulfate spike.

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

Cevabı ve açıklamayı göster

Cevap: Sample AS-442 contains a basaltic cryptotephra deposit.

Cevap

Sample AS-442 contains a basaltic cryptotephra deposit.
The deduction proceeds by indirect proof. Sample AS-442 corresponds to the mid-Holocene anomaly, meaning it must have either basaltic cryptotephra or high iridium, but not both. If sample AS-442 did not contain basaltic cryptotephra, it would necessarily contain high iridium. Under this scenario, because it has an anomalous sulfate spike without basaltic cryptotephra, it would have to be formed during non-explosive effusive volcanism (by the first premise). However, the third premise establishes that containing high iridium strictly precludes being formed during non-explosive effusive volcanism. Because this creates an impossible contradiction, the initial assumption must be false: sample AS-442 must contain a basaltic cryptotephra deposit.

Adım Adım Çözüm

1
Identify the known properties of sample AS-442 from the stimulus.
Sample AS-442 is from the Amundsen-Scott core, corresponds to the mid-Holocene climatic anomaly, and exhibits an anomalous sulfate spike.
Establishing the initial factual conditions sets the boundary for applying the conditional and disjunctive rules.
2
Apply the exclusive disjunction for mid-Holocene segments to sample AS-442.
Sample AS-442 must contain either basaltic cryptotephra OR high micro-meteoritic iridium, but cannot contain both.
The stimulus explicitly defines this mutual exclusivity for all mid-Holocene Amundsen-Scott segments.
3
Test the hypothetical assumption that sample AS-442 lacks basaltic cryptotephra.
If AS-442 lacks basaltic cryptotephra, it MUST have high iridium (by step 2) AND it MUST have been formed during non-explosive effusive volcanism (by the first premise, since it has a sulfate spike and no cryptotephra).
Evaluating the negation of the target condition reveals whether a logical contradiction arises.
4
Evaluate the result of step 3 against the third premise.
The third premise states that no segment with high iridium was formed during non-explosive effusive volcanism. This directly contradicts the outcome of step 3.
A valid deductive argument cannot result in mutually contradictory states.
5
Draw the necessary deductive conclusion by indirect proof (reductio ad absurdum).
Because assuming the absence of basaltic cryptotephra produces a direct contradiction, sample AS-442 must contain a basaltic cryptotephra deposit.
Eliminating one branch of a strict disjunction logically necessitates the truth of the other.

Anahtar Kavram

Deductive synthesis through conditional contraposition and proof by contradiction in exclusive disjunctions
Tahmini Süre:2m 0s
Soru 334Soru →

Hospital Administrator: A regional medical center cannot attain Tier-One trauma designation unless it maintains a board-certified trauma surgeon on site at all times and operates a dedicated blood transfusion unit. Valley General Hospital has just instituted continuous on-site staffing of board-certified trauma surgeons and completed the installation of a dedicated blood transfusion unit. It follows that Valley General will attain Tier-One trauma designation during its upcoming evaluation.

Which one of the following most accurately describes a flaw in the hospital administrator's reasoning?

Cevabı ve açıklamayı göster

Cevap: treats a set of conditions that are necessary for attaining the designation as though they are sufficient to guarantee it

Cevap

The argument treats conditions that are necessary for attaining the Tier-One trauma designation as though they are sufficient to guarantee that the designation will be awarded.
The administrator establishes that having on-site surgeons and a dedicated blood transfusion unit are mandatory minimum prerequisites for Tier-One designation. Meeting these necessary prerequisites does not establish that they are the only requirements needed for designation. By concluding that fulfilling these prerequisites guarantees designation, the argument mistakenly treats necessary conditions as sufficient.

Adım Adım Çözüm

1
Analyze the conditional relationship established in the first premise.
The phrase 'cannot attain... unless...' establishes that continuous on-site trauma surgeons and a dedicated blood transfusion unit are necessary conditions for Tier-One designation (Tier-One Designation → On-site Surgeons AND Transfusion Unit).
Accurately identifying conditional indicator words is essential for mapping the logical dependencies of the argument.
2
Evaluate the factual premise and the conclusion.
The premise establishes that Valley General satisfies both necessary conditions. The administrator concludes that Valley General will definitely achieve Tier-One designation.
This isolates the inferential gap between satisfying required prerequisites and guaranteeing the ultimate outcome.
3
Identify the reasoning error.
The author concludes that satisfying the necessary conditions guarantees the outcome (affirming the consequent / mistaking necessary for sufficient). Fulfilling minimum prerequisites does not ensure there are no additional requirements for designation.
A valid flaw description must precisely articulate this conditional error.

Anahtar Kavram

Flaw in the Reasoning: Confusing Necessary and Sufficient Conditions
Tahmini Süre:1m 30s
Soru 335Soru →

Paleontologist: The extinction of the Megalodon was not caused by a sudden global cooling event. Fossils of marine mammals—the Megalodon's primary prey—show no population decline in geological strata corresponding to the extinction period. Since its prey thrived, the theory that a catastrophic plunge in ocean temperatures starved the Megalodon is unfounded.

Statement: The discovery that the Megalodon inhabited deep, temperature-stable ocean trenches, whereas its prey occupied highly temperature-variable surface waters, significantly weakens the paleontologist's argument.

Cevabı ve açıklamayı göster

Cevap: False

Cevap

The statement is false. The proposed discovery actually strengthens the paleontologist's argument rather than weakening it.
The paleontologist concludes that global cooling did NOT cause the extinction. The new information shows the Megalodon lived in temperature-stable deep waters, meaning it would be physically insulated from a cooling event. This provides an additional, independent reason to believe cooling wasn't the cause. Because this fact bolsters the paleontologist's conclusion, it strengthens the argument. Therefore, the statement asserting that it weakens the argument is false.

Adım Adım Çözüm

1
Identify the author's main conclusion.
The conclusion is negative: A sudden global cooling event did NOT cause the Megalodon's extinction.
Isolating the exact conclusion is necessary to determine what type of evidence would weaken it.
2
Analyze the premises provided.
The primary premise is that the Megalodon's food source (marine mammals) survived the period without population decline.
Understanding the evidence helps evaluate the argument's core assumptions and vulnerabilities.
3
Evaluate the impact of the new information in the statement.
The new fact indicates the Megalodon lived in temperature-stable environments, protecting it from sudden oceanic cooling events.
We must determine how this new fact structurally interacts with the author's negative conclusion.
4
Determine if the information weakens the conclusion.
Because the new fact makes it even less likely that cooling killed the Megalodon, it provides secondary support to the author's claim. It strengthens the argument, meaning the statement that it weakens the argument is false.
A fact that strengthens an argument cannot fulfill a weaken prompt.

Anahtar Kavram

Recognizing opposite-task traps in arguments with negative conclusions.
Tahmini Süre:1m 30s
Soru 336Soru →

Wildlife Biologist: To prevent the spread of a fungal pathogen among endangered cave bats, conservationists installed heated artificial roosts in several winter hibernacula. Because the pathogen cannot survive temperatures above 18 degrees Celsius, the heated roosts successfully prevented fungal colonization on the bats occupying them. Nevertheless, bats utilizing the heated roosts suffered higher winter mortality rates than bats hibernating in unheated, fungus-free caves. Therefore, some environmental hazard inherent to the heated roosts is responsible for the elevated mortality.

Which of the following, if true, most seriously weakens the wildlife biologist's argument?

Cevabı ve açıklamayı göster

Cevap: Bats that enter hibernation with depleted fat reserves and severe physiological stress actively seek out warmer microclimates.

Cevap

Bats that enter hibernation with depleted fat reserves and severe physiological stress actively seek out warmer microclimates.
The correct answer weakens the argument by introducing an alternate cause rooted in selection bias. If bats that are already in critical metabolic distress preferentially seek warmer roosts, their higher mortality rate is a consequence of their prior health condition rather than an environmental hazard inherent to the heated roosts.

Adım Adım Çözüm

1
Isolate the argument's premises and main conclusion.
Premise: Bats in heated roosts avoided fungal colonization but had higher winter mortality than bats in unheated fungus-free caves. Conclusion: An environmental hazard inherent to the heated roosts caused the higher mortality.
Identifying the exact gap between the observed correlation and the causal conclusion is necessary to determine what would weaken the inference.
2
Identify the unstated assumption in the causal reasoning.
The biologist assumes that the bats using the heated roosts and those using unheated caves were comparable in health and survival probability prior to entering their respective hibernacula.
Causal claims based on group comparisons are vulnerable to selection bias and confounding baseline differences.
3
Select the statement that provides an alternative explanation for the mortality difference.
If stressed, malnourished bats selectively enter heated roosts, their pre-existing weakness accounts for the elevated mortality, eliminating the need to posit a hazard inherent to the roosts.
Demonstrating that the outcome was driven by self-selection rather than the roost environment directly undermines the causal conclusion.

Anahtar Kavram

Causal Reasoning and Selection Bias
Tahmini Süre:1m 30s
Soru 337Soru →

The Municipal Transit Authority maintains the following operational regulations for municipal bus routes:

• Every bus route that operates along the North Ridge corridor is classified as a high-altitude transit line.
• Any transit line classified as a high-altitude transit line requires winterized traction control systems.
• No transit line that requires winterized traction control systems is authorized for solo-operator night shifts unless it maintains dedicated thermal battery preheating.
• Route 42 operates along the North Ridge corridor and is authorized for solo-operator night shifts.

If the statements above are true, which one of the following must be true on the basis of them?

Cevabı ve açıklamayı göster

Cevap: Route 42 maintains dedicated thermal battery preheating.

Cevap

Route 42 maintains dedicated thermal battery preheating.
The conclusion that Route 42 maintains dedicated thermal battery preheating is logically guaranteed. Route 42 operates on the North Ridge corridor, which means it is a high-altitude line and therefore requires winterized traction control. Under the regulations, any line requiring winterized traction control cannot be authorized for solo-operator night shifts unless it maintains dedicated thermal battery preheating. Because Route 42 is authorized for those night shifts, it must maintain dedicated thermal battery preheating.

Adım Adım Çözüm

1
Map the conditional relationships established by the stimulus rules
North Ridge corridor → High-altitude transit line → Requires winterized traction control. (Requires winterized traction control AND Authorized for solo-operator night shifts) → Dedicated thermal battery preheating.
Establishing the chain of necessary conditions allows direct evaluation of specific cases.
2
Apply the factual premises regarding Route 42 to the conditional chain
Route 42 is on North Ridge → Route 42 is a high-altitude line → Route 42 requires winterized traction control.
Determines which properties Route 42 necessarily possesses based on its route.
3
Synthesize the traction control requirement with the authorization rule
Since Route 42 requires winterized traction control and is authorized for solo-operator night shifts, it must satisfy the necessary condition: maintaining dedicated thermal battery preheating.
Completes the deductive inference guaranteed by the premises.

Anahtar Kavram

Deductive Conditional Chaining and Necessary Condition Derivation
Tahmini Süre:1m 15s
Soru 338Soru →

Under the Northern Abyssal Maritime Protocol, every deep-sea exploration vessel operating in the Northern Abyssal Zone that is equipped with autonomous acoustic mapping sensors is required to carry a dual-redundant power core. No vessel carrying a dual-redundant power core is permitted to enter the benthic sanctuary unless it has received benthic environmental clearance. Furthermore, every vessel that has received benthic environmental clearance has completed a closed-loop coolant inspection. The research vessel Vanguard operates in the Northern Abyssal Zone and is equipped with autonomous acoustic mapping sensors, but it has not completed a closed-loop coolant inspection.

Based on the information above, which of the following statements must be true? (Select all that apply)

Geçerli olan tümünü seçin

Cevabı ve açıklamayı göster

Cevap: The Vanguard carries a dual-redundant power core.; The Vanguard is not permitted to enter the benthic sanctuary.

Cevap

The statements indicating that the Vanguard carries a dual-redundant power core and that the Vanguard is not permitted to enter the benthic sanctuary must both be true.
The premises establish two deductive chains: first, the Vanguard's location and equipment satisfy the sufficient condition requiring a dual-redundant power core; second, by contrapositive, the absence of a coolant inspection proves the Vanguard lacks environmental clearance, which in turn bars any vessel with a dual-redundant power core from entering the sanctuary.

Adım Adım Çözüm

1
Deduce the power core status of the Vanguard from the first rule.
The Vanguard is established to carry a dual-redundant power core.
The stimulus specifies that any vessel in the Northern Abyssal Zone equipped with acoustic mapping sensors must carry a dual-redundant power core, and the Vanguard satisfies both trigger conditions.
2
Apply the contrapositive to the coolant inspection rule.
The Vanguard has not received benthic environmental clearance.
Since benthic environmental clearance requires completing a closed-loop coolant inspection, failing to complete the inspection guarantees that clearance was not received.
3
Evaluate the entry restriction for the benthic sanctuary.
The Vanguard is prohibited from entering the benthic sanctuary.
Any vessel with a dual-redundant power core cannot enter without clearance; having established that the Vanguard has the core and lacks clearance, it cannot enter.

Anahtar Kavram

Deductive Conditional Chaining and Contrapositive Inference
Tahmini Süre:2m 0s
Soru 339Soru →

Historian: Excavations at the eighth-century settlement of Dunhaven revealed subterranean storage pits containing charred barley alongside rye grains infested with a species of grain weevil that reproduces exclusively in stored grain. Because no physical traces of aboveground storage structures were found at Dunhaven, some archaeologists have concluded that the settlement stored all of its harvested grain exclusively in these underground pits. However, this specific weevil species cannot survive winters in the subterranean humidity characteristic of Dunhaven's clay soil. Therefore, Dunhaven's residents must have utilized aboveground grain storage facilities that have left no trace in the archaeological record.

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

Cevabı ve açıklamayı göster

Cevap: The infested rye grains found at Dunhaven had been stored at the settlement through at least one winter season.

Cevap

The infested rye grains found at Dunhaven had been stored at the settlement through at least one winter season.
The argument concludes that aboveground storage must have existed solely based on the fact that weevils cannot survive winter in subterranean clay pits. This inference holds only if the weevils were present during a winter at Dunhaven. If the infested rye was consumed, processed, or discarded before winter arrived, the weevils never had to survive an underground winter, removing any necessity for aboveground storage structures.

Adım Adım Çözüm

1
Identify the conclusion and premises of the stimulus
Conclusion: Dunhaven's residents must have used unrecorded aboveground grain storage facilities. Premises: Grain weevils reproduce only in stored grain; they cannot survive winter in the humid underground pits at Dunhaven.
Establishing the logical gap between the premises and the conclusion isolates what must be assumed.
2
Evaluate the missing link required for the premise about winter survival to support the conclusion
The argument infers that aboveground storage was necessary because weevils cannot survive winter underground. For this limitation to force an aboveground facility, the weevils must have actually had to survive a winter at Dunhaven.
If the grain was not kept through a winter, winter survival constraints cannot necessitate alternative winter storage.
3
Apply the Negation Test to verify necessity
Negation: The infested rye grains found at Dunhaven were NOT stored at the settlement through any winter season. If true, the weevils never needed to survive a winter at Dunhaven, eliminating the need for aboveground winter storage and collapsing the conclusion.
A necessary assumption must fatally undermine the argument when negated.

Anahtar Kavram

Necessary Assumption (Defender Model)
Tahmini Süre:1m 20s
Soru 340Soru →

Agronomists observed that blueberry plots treated with crushed pecan shell mulch produced 25 percent higher fruit yields than untreated bare soil plots. The agronomists concluded that nutrients released into the soil by decomposing pecan shells caused the increase in yield.

True or False: The finding that blueberry plots covered with an inert synthetic ground cover—which provides identical moisture retention and weed suppression to pecan shells but releases zero nutrients—produced yields no higher than untreated bare soil plots strengthens the agronomists' argument.

Cevabı ve açıklamayı göster

Cevap: True

Cevap

True
The claim is evaluated as True because the supplementary finding functions as a negative control. By showing that the yield gain does not occur under identical non-nutritive physical conditions, the finding eliminates moisture retention and weed suppression as alternate causes, directly boosting the plausibility of the nutrient-based explanation.

Adım Adım Çözüm

1
Identify the conclusion and premises in the argument.
Premise: Blueberry plots with pecan shell mulch yielded 25% more fruit than bare soil. Conclusion: Nutrients from decomposing pecan shells caused the yield increase.
Clarifying the core claim isolates the exact causal relationship that must be supported.
2
Identify the unstated assumption and potential alternative explanations.
The argument assumes that non-nutritional properties of the mulch (such as weed control or moisture retention) were not the true causes of the increased yield.
Causal arguments on the LSAT are vulnerable to alternate causes; eliminating an alternate cause strengthens the conclusion.
3
Evaluate the impact of the supplementary statement.
The statement acts as a control test showing that when physical benefits are present without nutrients, yield does not increase.
Eliminating alternative mechanisms validates the author's proposed causal factor, confirming that the statement strengthens the argument.

Anahtar Kavram

Strengthening a causal conclusion by ruling out alternative explanations through a control condition
Tahmini Süre:45s
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Logical Reasoning Alıştırma Soruları — LSAT — Sayfa 17 | Examkin