Tüm alıştırma soruları

3960 soru

Soru 21Soru →

Maritime Regulator: The proposed automated docking protocol relies entirely on continuous satellite telemetry rather than traditional visual guidance from harbormasters. Therefore, mandating this new protocol for all commercial vessels entering the bay will definitively decrease the frequency of docking collisions and subsequently reduce the port's overall operational liabilities.

Which of the following statements function as required assumptions to logically bridge the gaps in the regulator's argument? Select all that apply.

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Cevap: Relying on continuous satellite telemetry rather than traditional visual guidance leads to fewer docking collisions.; A decrease in the frequency of docking collisions will result in a reduction of the port's overall operational liabilities.

Cevap

The correct selections are the statement connecting satellite telemetry to fewer collisions, and the statement connecting decreased collisions to reduced operational liabilities.
The argument contains a chain of reasoning with two explicit logical leaps. The author moves from a factual premise (the protocol uses satellite telemetry instead of visual guidance) to a claim about safety (fewer collisions) and then to a claim about finances (reduced liabilities). For the argument to be logically valid, it strictly requires assumptions that connect these disparate concepts together. The correct statements act as these necessary bridges.

Adım Adım Çözüm

1
Identify the core premises of the argument.
Premise: The new protocol uses satellite telemetry instead of visual guidance.
Deconstructing the argument structure is the first step in finding logical gaps.
2
Identify the core conclusions of the argument.
Conclusion: The new protocol will decrease docking collisions AND reduce overall operational liabilities.
Understanding exactly what the author is trying to prove reveals which terms are 'rogue' or unsupported.
3
Identify new terms in the conclusion that do not appear in the premises.
The concepts of 'decreased frequency of docking collisions' and 'reduced operational liabilities' are introduced in the conclusion without prior support.
In a Supporter Assumption question, rogue terms in the conclusion must be explicitly linked to the premises.
4
Formulate the required bridging statements.
Bridge 1: Satellite telemetry must lead to fewer collisions. Bridge 2: Fewer collisions must lead to reduced liabilities.
These connections are absolutely necessary for the argument's logic to flow from the premises to the stated conclusions.

Anahtar Kavram

Identifying multiple logical gaps in an argument and selecting the exact supporter assumptions required to link rogue conclusion elements back to the premises.
Soru 22Soru →

The annual spring festival will definitely not be held in the town square this year. We know this because the festival is held in the square whenever the municipal budget runs a surplus and the mayor's office approves the permit. However, the municipal budget is not running a surplus this year.

Which one of the following arguments exhibits a flawed pattern of reasoning most similar to that exhibited by the argument above?

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Cevap: Whenever the beta testing phase finds no critical bugs and the marketing campaign is finalized, the new software update is released on schedule. Yet, because the marketing campaign has not been finalized, the software update will not be released on schedule.

Cevap

The argument concluding that the software update will not be released on schedule because the marketing campaign has not been finalized.
The stimulus commits an illegal negation by treating a compound sufficient condition as a necessary one. It establishes that two things together (budget surplus AND permit approval) guarantee an outcome. It then points out that one of those things didn't happen, and concludes the outcome won't happen. The correct answer has the exact same structure: it establishes that two things (no bugs AND marketing finalized) guarantee an outcome (released on schedule), notes that one didn't happen (marketing not finalized), and relies on flawed logic to conclude the outcome will not happen.

Adım Adım Çözüm

1
Analyze the stimulus to identify the conclusion and premises.
Conclusion: The festival will not be held in the square. Premise 1: If budget runs a surplus AND permit is approved, then the festival is held in the square. Premise 2: The budget is not running a surplus.
Deconstructing the argument into formal logic is necessary to identify the exact structural flaw before examining the choices.
2
Identify the logical flaw in the stimulus.
The flaw is an illegal negation of a compound sufficient condition. The argument assumes that because one required part of the sufficient condition failed, the necessary result cannot occur, ignoring that there could be alternate ways to trigger the result.
Knowing the precise flaw prevents being distracted by arguments that are flawed but structurally different.
3
Evaluate the answer choices to find the matching abstract structure.
The software update argument matches: Premise 1 is (No bugs AND marketing finalized) -> released on schedule. Premise 2 is ~Marketing finalized. Conclusion is ~Released on schedule.
The correct answer in a Parallel Flaw question must match both the specific logical error and the structural components of the original argument.

Anahtar Kavram

Parallel Flaw - Illegal Negation of a Compound Condition
Soru 23Soru →

Agronomist: In a multi-year agricultural study across several commercial grain farms, fields planted with hairy vetch as a winter cover crop produced subsequent corn yields that were on average 20 percent higher than those from fields left fallow during the winter. Because hairy vetch is known to fix atmospheric nitrogen into the soil, this substantial increase in yield must be directly attributable to the additional nitrogen provided by the cover crop.

Which of the following statements, if true, most seriously weaken the agronomist's argument? Select all that apply.

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Cevap: Fields planted with hairy vetch retained significantly higher soil moisture throughout early summer droughts than fallow fields, and moisture retention is the primary determinant of corn yields in these regions.; Farmers participating in the study applied identical high levels of synthetic nitrogen fertilizer to all fields, raising soil nitrogen well above the maximum threshold usable by corn plants.

Cevap

The argument is weakened by the statement establishing soil moisture retention as an alternate cause for the higher yields, as well as the statement demonstrating that preexisting synthetic fertilizer levels already saturated the crops' nitrogen requirements.
The correct statements undermine the argument by challenging the causal attribution: one introduces an alternative causal factor (enhanced moisture retention during critical drought periods) that fully accounts for the yield disparity, while the other shows that nitrogen levels were already saturated beyond the threshold of utility, eliminating the possibility that supplemental nitrogen caused the yield improvement.

Adım Adım Çözüm

1
Identify the conclusion and the supporting premises in the stimulus
Premise: Fields with hairy vetch cover crops produced 20 percent higher corn yields than fallow fields. Premise: Hairy vetch fixes atmospheric nitrogen. Conclusion: The yield increase must be directly attributable to the additional nitrogen.
Isolating the structural components reveals the core causal claim made by the author.
2
Identify the underlying assumptions and potential points of vulnerability
The author assumes that nitrogen fixation is the only relevant difference caused by the cover crop and that additional nitrogen was capable of driving yield gains in this setting.
Causal arguments can be weakened by offering an alternative cause for the effect or showing that the proposed cause could not have produced the effect.
3
Evaluate each option to find all statements that undermine the causal connection
Introducing moisture retention as the decisive factor provides an alternative explanation, while showing that nitrogen was already supplied past the crop's uptake capacity negates the proposed causal mechanism.
Both findings directly attack the link between the cover crop's nitrogen fixation and the observed yield increase.

Anahtar Kavram

Weakening causal arguments through alternative explanations and demonstrating the ineffectiveness of the proposed cause
Tahmini Süre:1m 30s
Soru 24Soru →

An environmental audit of reclaimed sub-boreal wetland zones established the following criteria for ecosystem stabilization:

• Any wetland zone that undergoes successful peat layer restoration exhibits stable anaerobic methanogenesis, unless it experiences persistent sulfur runoff.
• Every wetland zone that exhibits stable anaerobic methanogenesis maintains a neutral pH level throughout its rooting substrate.
• No wetland zone that maintains a neutral pH level in its rooting substrate supports the proliferation of invasive reed canary grass.
• During the previous assessment cycle, Zone 14 underwent successful peat layer restoration and did not experience persistent sulfur runoff.

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

Geçerli olan tümünü seçin

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Cevap: Zone 14 maintains a neutral pH level throughout its rooting substrate.; Any wetland zone in the audit that supports the proliferation of invasive reed canary grass does not exhibit stable anaerobic methanogenesis.

Cevap

The statements establishing that Zone 14 maintains a neutral pH level throughout its rooting substrate and that any wetland zone supporting invasive reed canary grass proliferation does not exhibit stable anaerobic methanogenesis must both be true.
The deduction concerning Zone 14 directly follows from a complete forward chain through the conditional rules triggered by its factual premises. The deduction concerning any zone with canary grass proliferation represents a valid contrapositive linking the absence of proliferation back to the absence of stable anaerobic methanogenesis.

Adım Adım Çözüm

1
Diagram the formal conditional rules from the stimulus.
Rule 1: (Peat Restoration AND NOT Sulfur Runoff) → Stable Methanogenesis. Rule 2: Stable Methanogenesis → Neutral pH. Rule 3: Neutral pH → NOT Invasive Canary Grass Proliferation.
Establishing explicit conditional chains allows for unambiguous forward deductions and contrapositives.
2
Evaluate the factual findings regarding Zone 14.
Zone 14 satisfies both components of the antecedent in Rule 1, establishing that Zone 14 exhibits Stable Methanogenesis → Neutral pH → NOT Invasive Canary Grass Proliferation.
Modus ponens guarantees each successive necessary condition for Zone 14.
3
Derive universal contrapositive inferences for the entire audited population.
By linking Rule 2 and Rule 3: Stable Methanogenesis → NOT Invasive Canary Grass Proliferation. The contrapositive is: Invasive Canary Grass Proliferation → NOT Stable Methanogenesis.
A conditional claim and its contrapositive are logically equivalent.

Anahtar Kavram

Deductive Conditional Chaining and Contrapositive Inference
Tahmini Süre:2m 0s
Soru 25Soru →

Economist: Software developers routinely release preliminary versions of their applications to a restricted user base. This practice allows developers to identify unforeseen design flaws through actual user testing before a general release. Analogously, the central government should implement its proposed comprehensive corporate tax overhaul in just two mid-sized provinces first. Doing so would allow policymakers to observe real-world economic impacts and correct any legislative flaws before applying the new tax code nationwide.

The economist's argument is most vulnerable to criticism on the grounds that it

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Cevap: fails to consider that, unlike a preliminary software release, a localized tax trial can cause businesses to relocate outside the test area, thereby distorting the very observations the trial is designed to gather.

Cevap

The correct answer identifies that the argument overlooks a critical disanalogy: a localized tax trial can cause capital relocation (which ruins the data gathering process), whereas software testing does not cause a comparable distortion.
This option successfully weakens the argument by pointing out a critical disanalogy between the two situations. The stated purpose of both trials is to observe real-world impacts to identify flaws. However, if a localized tax trial causes businesses to move away to avoid the tax, the economic data gathered will be heavily distorted by this artificial border effect. Because software tests do not suffer from a comparable 'relocation' distortion that ruins the test data, the analogy fails to support the conclusion that the tax trial would yield accurate, useful observations.

Adım Adım Çözüm

1
Analyze the argument's core structure and method.
The economist argues by analogy: just as software developers use restricted beta releases to find and fix flaws, the government should use a geographically restricted tax trial to find and fix legislative flaws.
Understanding the base case (software) and target case (tax policy) is necessary for evaluating the strength of an analogy.
2
Identify the conclusion and the supporting premises.
Premise: Restricted software releases help find design flaws. Conclusion: A restricted tax rollout will help policymakers observe impacts and fix legislative flaws before national implementation.
Isolating the conclusion clarifies what the argument is trying to prove and how the analogy is supposed to support it.
3
Evaluate the strength of the analogy by looking for relevant differences.
An argument by analogy is most vulnerable if there is a relevant difference (disanalogy) between the two cases that directly undermines the conclusion.
We must look for a difference that specifically prevents the tax trial from achieving its stated goal of accurate economic observation.
4
Select the option that exposes the critical disanalogy.
The option stating that businesses might relocate outside the test area shows how the tax trial would yield distorted, inaccurate data, unlike a software test.
This directly attacks the analogy's assumption that the two localized trials would function similarly in successfully revealing flaws without inherently corrupting the test environment.

Anahtar Kavram

Evaluating Argument by Analogy (Identifying Relevant Disanalogies)
Soru 26Soru →

City Council Member: To reduce the alarming rate of bicycle thefts in our city, we should implement a mandatory bicycle registration program, much like our existing automobile registration system. Our automobile registration requires owners to display visible plates and maintains easily traceable records in a central database; this system has made stealing cars incredibly difficult and risky. Similarly, requiring visible registration tags and maintaining a database of bicycle owners will effectively deter bicycle thieves.

Which of the following, if true, points out the most serious weakness in the city council member's argument?

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Cevap: Unlike automobiles, which have deeply integrated vehicle identification numbers, bicycles can have registration tags and serial numbers quickly and permanently removed by a thief.

Cevap

The statement pointing out that unlike automobiles, bicycles can have their registration tags easily removed.
The correct answer directly attacks the core assumption of the analogy. For the bicycle registration program to mimic the success of the automobile program, the tracking mechanisms must be similarly robust. By pointing out that bicycle tags can be easily and permanently removed—unlike deeply integrated car identification numbers—this option demonstrates a critical difference (disanalogy) between the two cases, effectively destroying the argument's predictive power.

Adım Adım Çözüm

1
Identify the conclusion of the argument.
The conclusion is that requiring visible registration tags and a database will effectively deter bicycle thieves.
Understanding the main point is required to know what needs to be weakened.
2
Identify the premises and method of reasoning.
The author uses an argument by analogy: because a similar system worked for cars (due to visible plates and traceable records), it will work for bicycles.
Identifying the analogy highlights the core structural assumption: that cars and bicycles are similar enough in the relevant ways for the plan to succeed.
3
Evaluate the analogy for potential flaws (disanalogies).
A strong weaken answer will show a relevant difference between cars and bicycles regarding traceability and registration tags.
If the two subjects differ significantly regarding the mechanism of success, the analogy falls apart.
4
Select the option that breaks the analogy.
The correct option points out that bicycle tags can be easily removed, whereas car identifiers are deeply integrated.
This directly attacks the premise that bicycle registration will function just like car registration in practice.

Anahtar Kavram

Identifying a relevant disanalogy to weaken an argument by analogy.
Tahmini Süre:1m 30s
Soru 27Soru →

Political Scientist: A thriving democracy cannot exist without a highly educated electorate. Critics of the proposed national curriculum argue that its heavy emphasis on critical thinking and media literacy is a waste of resources. But this curriculum will undeniably result in a highly educated electorate. Therefore, the adoption of this curriculum will inevitably result in a thriving democracy.

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

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Cevap: infers the occurrence of a phenomenon solely from the presence of a precondition without which that phenomenon could not occur

Cevap

The argument infers the occurrence of a phenomenon solely from the presence of a precondition without which that phenomenon could not occur.
The correct answer accurately describes an illegal reversal in abstract terms. The argument states that a highly educated electorate is required (a necessary precondition) for a thriving democracy. It then establishes that the curriculum will produce a highly educated electorate, and concludes this alone is enough to guarantee (infer the occurrence of) a thriving democracy. This illicitly treats a necessary condition as if it were a sufficient condition.

Adım Adım Çözüm

1
Analyze the first sentence to identify the primary conditional relationship.
A thriving democracy requires a highly educated electorate (Thriving Democracy -> Highly Educated Electorate).
The phrase 'cannot exist without' introduces a necessary condition, making a highly educated electorate the precondition.
2
Analyze the remaining premises to identify the secondary relationship.
The proposed curriculum guarantees a highly educated electorate (Curriculum -> Highly Educated Electorate).
The scientist explicitly states the curriculum will 'undeniably result in' this outcome.
3
Identify the argument's final conclusion.
The argument concludes that the curriculum guarantees a thriving democracy (Curriculum -> Thriving Democracy).
This is indicated by the transition phrase 'Therefore, the adoption of this curriculum will inevitably result in'.
4
Compare the premises to the conclusion to identify the logical gap.
The argument assumes that because the curriculum leads to a highly educated electorate, it must automatically lead to a thriving democracy.
This logic incorrectly assumes that a highly educated electorate is sufficient for a thriving democracy (Highly Educated Electorate -> Thriving Democracy), which is an illegal reversal of the first premise.

Anahtar Kavram

Illegal Reversal (Treating a Necessary Condition as Sufficient)
Soru 28Soru →

In order to qualify for the accelerated development grant, a local infrastructure project must be classified as high-priority by the regional council and must secure matching private investments. Any infrastructure project that secures matching private investments is subject to the strict environmental oversight of the federal preservation board. However, no project proposed by the municipal transit authority is subject to this strict environmental oversight. Nevertheless, some projects proposed by the municipal transit authority are classified as high-priority by the regional council.

If the statements above are true, which one of the following cannot be true?

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Cevap: A project proposed by the municipal transit authority qualifies for the accelerated development grant.

Cevap

The option stating that a project proposed by the municipal transit authority qualifies for the accelerated development grant cannot be true.
The stimulus establishes a conditional chain that rules out municipal transit authority projects from qualifying for the grant. To qualify for the accelerated development grant, a project must secure matching private investments. Any project with matching private investments is subject to strict environmental oversight. Therefore, qualifying for the grant strictly requires being subject to environmental oversight. However, the stimulus explicitly states that no project proposed by the municipal transit authority is subject to this oversight. Consequently, no municipal transit authority project can ever secure matching private investments, making it impossible for any such project to satisfy the necessary conditions for the grant.

Adım Adım Çözüm

1
Map the conditions required to qualify for the grant.
Grant -> High-Priority AND Matching Investments.
Translating the text into formal logic simplifies the complex conditional rules.
2
Map the consequences of securing matching investments.
Matching Investments -> Strict Oversight.
Connecting terms allows us to build a deductive chain.
3
Map the rules regarding the municipal transit authority.
Transit Authority -> NOT Strict Oversight. (Additionally, Transit Authority -some- High-Priority).
Identifying absolute constraints on specific entities reveals logical impossibilities.
4
Combine the rules to test if a transit authority project can logically qualify for the grant.
Transit Authority -> NOT Strict Oversight -> NOT Matching Investments -> NOT Grant.
Since transit projects cannot secure matching investments, they fail a necessary condition for the grant, making their qualification logically impossible.

Anahtar Kavram

Chaining conditional statements to identify a logically impossible outcome.
Tahmini Süre:2m 0s
Soru 29Soru →

Analyze the logical structure of the following counterexamples. Pair each argument in the primary list with the argument in the secondary list that employs an identical method of refutation.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Linguists claim that all creole languages inherently lack complex morphological inflections. However, Chavacano is a widely spoken creole that possesses a highly developed system of verbal affixation.
Critics argue that implementing rent control invariably reduces housing availability by disincentivizing new construction. However, when Springville enacted strict rent controls, the housing supply expanded rapidly even as new construction permits plummeted.
Historians assert that only societies with a centralized agrarian state could develop written legal codes. Yet, the ancient nomadic tribes of the steppes, which entirely lacked centralized agriculture, utilized a sophisticated written legal framework.
Sociologists propose that no social movement can achieve lasting legislative change without securing the backing of major media conglomerates. However, the grassroots labor strikes of the 1930s secured landmark labor laws while facing unanimous opposition from major media outlets.

Eşleşmeler

Cevabı ve açıklamayı göster

Cevap

The correct pairings match arguments based on their abstract refutation structure: the creole argument matches the subterranean mammals argument; the rent control argument matches the corporate mergers argument; the historians argument matches the geologists argument; and the sociologists argument matches the astrophysicists argument.
Each correct pairing links two arguments that employ the exact same logical architecture to refute a claim. The 'creole' and 'mammals' arguments both disprove a universal negative claim. The 'rent control' and 'mergers' arguments both disprove a causal relationship where the expected mechanism is demonstrably present but the effect is absent. The 'historians' and 'geologists' arguments both disprove an 'only' claim by showing the effect occurring without the required condition. Finally, the 'sociologists' and 'astrophysicists' arguments both disprove a 'without' conditional by demonstrating success in the explicit absence of the condition.

Adım Adım Çözüm

1
Analyze the logical structure of the 'creole languages' counterexample.
Structure identified: Refutation of 'All A lack B' with 'Instance C is A and has B'.
Identifying the abstract logical structure is required to find its exact parallel counterpart.
2
Identify the matching structure among the secondary list for the first argument.
The 'subterranean mammals' argument matches this structure precisely, refuting a universal negative with a single positive instance.
Matching the abstract structural components establishes the correct pair.
3
Analyze the 'rent control' argument's refutation method.
Structure identified: X is claimed to cause Y via mechanism Z. Counterexample shows X and Z occurring, but not Y.
Capturing the nuanced role of the mechanism (Z) is crucial to avoid misidentifying the parallel argument.
4
Locate the parallel structure for the 'rent control' argument.
The 'corporate mergers' argument aligns perfectly, showing a merger (X) and monopoly (Z) without a decrease in quality (Y).
Both demonstrate a failed causal prediction despite the presence of the explicitly assumed causal mechanism.

Anahtar Kavram

Parallel Reasoning with Counterexamples

Alternatif Yöntem

Instead of analyzing the primary list first, try symbolizing each argument using formal logic notation (e.g., A -> B). This strips away the context entirely and makes the structural matches visually obvious.
Tahmini Süre:3m 0s
Soru 30Soru →

A comprehensive urban redevelopment plan will successfully revitalize the downtown district only if it includes substantial financial incentives for small businesses. The city council's newly proposed redevelopment plan features unprecedented financial incentives specifically designed to attract and retain small businesses. Thus, the council's plan is certain to successfully revitalize the downtown district.

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

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Cevap: It treats a condition that is necessary for a particular outcome as though it were sufficient to guarantee that outcome.

Cevap

It treats a condition that is necessary for a particular outcome as though it were sufficient to guarantee that outcome.
The author establishes that including substantial financial incentives is a requirement (a necessary condition) for a redevelopment plan to revitalize the downtown district. The author then observes that the city council's plan includes these incentives and concludes that the plan will therefore be successful. This confuses a condition that is required for a result with a condition that guarantees the result.

Adım Adım Çözüm

1
Identify the argument's main conclusion.
The conclusion is: 'the council's plan is certain to successfully revitalize the downtown district.'
Isolating the conclusion is necessary to understand the claim the author is trying to prove.
2
Analyze the premises supporting the conclusion.
The first premise states that revitalization occurs 'only if' there are financial incentives. The second premise states that the council's plan includes these financial incentives.
Understanding the precise wording of the premises helps reveal the conditional relationship (A only if B).
3
Evaluate the logical connection between the premises and conclusion.
The phrase 'only if' introduces a necessary condition. The author proves the necessary condition is met, and mistakenly concludes that the sufficient condition (revitalization) is guaranteed to happen.
Identifying this gap reveals the classic necessary versus sufficient condition flaw, commonly known as an illegal reversal.

Anahtar Kavram

Necessary vs. Sufficient Condition Flaws
Soru 31Soru →

According to the newly ratified Outer Space Mining Treaty, securing a commercial extraction license on the lunar surface requires that a corporation either establish an autonomous life-support habitat or formally partner with a state-sponsored space agency.

Which one of the following statements logically follows from the treaty's requirement?

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Cevap: If a corporation neither establishes an autonomous life-support habitat nor formally partners with a state-sponsored space agency, it will not secure a commercial extraction license on the lunar surface.

Cevap

The statement that logically follows is: 'If a corporation neither establishes an autonomous life-support habitat nor formally partners with a state-sponsored space agency, it will not secure a commercial extraction license on the lunar surface.'
The correct answer accurately applies formal logic and De Morgan's laws to create a valid contrapositive. The original premise dictates: License → (Habitat OR Partner). The contrapositive requires reversing the direction and negating both sides. Crucially, negating an 'OR' statement transforms it into an 'AND' statement. Therefore, the valid inference is: If NOT Habitat AND NOT Partner (phrased as 'neither... nor'), then NOT License.

Adım Adım Çözüm

1
Identify the logical structure of the original rule in the stimulus.
Sufficient condition: Securing a commercial extraction license. Necessary condition: Establishing a habitat OR partnering with a space agency.
Mapping the exact formal logic relationship is required before evaluating conditional deductions.
2
Formulate the logical contrapositive of the rule.
To find the contrapositive, reverse the terms and negate both sides. Negating the 'OR' statement requires De Morgan's laws: 'NOT (Habitat OR Partner)' becomes 'NOT Habitat AND NOT Partner'.
The only statement that definitively must be true based on a conditional premise is its logically valid contrapositive.
3
Match the formulated contrapositive to the answer choices.
The correct deduction is: If a corporation does NOT establish a habitat AND does NOT partner with an agency (neither... nor), then it CANNOT secure a license.
This eliminates choices that contain formal logical fallacies such as mistaken reversals, mistaken negations, or incomplete applications of De Morgan's laws.

Anahtar Kavram

Forming valid contrapositives from compound conditional statements using De Morgan's laws.
Soru 32Soru →

An educational researcher reviewed data from a large district of elementary school students. The researcher noted that students who regularly participate in after-school chess clubs consistently achieve higher grades in computer science classes. Based on this observation, the researcher concluded that playing chess directly enhances a student's computer science abilities.

Which of the following statements, if true, expose the flaw in the argument by providing a valid alternative explanation for the observed correlation? Select all that apply.

Geçerli olan tümünü seçin

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Cevap: Students who already possess strong analytical skills necessary for computer science are naturally drawn to joining chess clubs.; Schools that offer after-school chess clubs are generally located in districts with high funding, which also allows them to provide superior computer science instruction.

Cevap

The correct statements are the ones that suggest students' analytical skills draw them to chess (reverse causation) and that well-funded schools provide both chess clubs and better instruction (third variable).
The correct options directly undermine the researcher's conclusion by demonstrating classic alternative explanations for a correlation. One option demonstrates a 'third variable' scenario where district funding acts as the true cause for both the presence of chess clubs and high grades. The other option demonstrates 'reverse causality', suggesting that students who are already good at computer science are simply more inclined to play chess.

Adım Adım Çözüm

1
Identify the argument's premises and conclusion.
Premise: There is a correlation between chess club participation and high computer science grades. Conclusion: Playing chess causes better computer science abilities.
Deconstructing the argument is necessary to evaluate its logical structure.
2
Identify the logical flaw.
The argument assumes causation based solely on correlation.
Recognizing the correlation vs. causation flaw tells you what kind of evidence would undermine the conclusion.
3
Evaluate the options for valid alternative explanations.
Find options that present a third variable causing both phenomena or suggest the causal relationship is backward.
Alternative explanations directly weaken a causal conclusion by showing the correlation could exist for other reasons.

Anahtar Kavram

Correlation vs. Causation
Soru 33Soru →

A city council should approve a commercial development in the historic district only if the development preserves the original facades of all existing structures. Furthermore, the development should be approved only if it meets at least one of the following two conditions: it provides affordable housing units, or it does not require a municipal tax subsidy. However, if a development preserves the original facades, provides affordable housing, and does not require a tax subsidy, the council must approve it.

Which one of the following judgments most closely conforms to the principle stated above?

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Cevap: The Silver Tower development was approved by the city council but required a municipal tax subsidy. Therefore, the Silver Tower development must have provided affordable housing units and preserved the original facades of all existing structures.

Cevap

The judgment regarding the Silver Tower development, which concludes that because it was approved but required a municipal tax subsidy, it must have provided affordable housing units and preserved the original facades.
The correct answer accurately applies the necessary conditions for approval established in the stimulus. We are told that approval requires preserving original facades AND either providing affordable housing or not requiring a tax subsidy. Because this specific development was approved, all of these necessary conditions must have been met. Since it did require a tax subsidy, it failed one half of the 'either/or' condition. Therefore, to satisfy the logical requirement, it absolutely must have fulfilled the other half by providing affordable housing. It also must have met the baseline requirement of preserving the original facades.

Adım Adım Çözüm

1
Diagram the necessary conditions for approval.
Approval (A) → Preserves Facades (PF) AND [Provides Affordable Housing (AH) OR Does Not Require Subsidy (~TS)]
The phrase 'only if' introduces necessary conditions that must be met for approval to be granted.
2
Diagram the sufficient condition for approval.
(PF AND AH AND ~TS) → Approval (A)
The phrase 'if' introduces a sufficient condition, and 'must approve it' establishes the guaranteed outcome.
3
Analyze the correct judgment using the established necessary conditions.
The Silver Tower was approved (A is true). Therefore, PF must be true, AND the disjunction (AH OR ~TS) must be true.
When a sufficient condition (Approval) is met, all of its necessary conditions are guaranteed to occur.
4
Evaluate the disjunction based on the provided facts.
The Silver Tower required a municipal tax subsidy, meaning ~TS is false. For the statement (AH OR ~TS) to remain true, AH must be true.
In formal logic, if an 'OR' statement is true but one of its components is false, the other component must definitively be true.
5
Conclude the final logical requirement.
The development must have preserved facades (PF) AND provided affordable housing (AH).
This perfectly matches the deductive conclusion drawn in the correct judgment.

Anahtar Kavram

Applying complex formal logic, specifically tracking compound necessary and sufficient conditions, evaluating disjunctions (OR statements), and forming proper contrapositives.
Soru 34Soru →

Paleoecologist: Marine sediment cores from the Subarctic Pacific show that during historical epochs characterized by high atmospheric dust deposition, the ratio of preserved giant virus DNA fragments to diatom microfossils was more than four times higher than during dust-poor epochs. Because atmospheric dust delivers bioavailable iron that accelerates diatom reproduction, researchers concluded that iron enrichment intensifies the rate of viral infection among diatoms.

Which one of the following is an assumption on which the researchers' conclusion depends?

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Cevap: The giant virus DNA fragments detected in the sediment cores did not predominantly originate from viruses that infect marine organisms other than diatoms.

Cevap

The argument depends on the assumption that the giant virus DNA fragments detected in the sediment cores did not predominantly originate from viruses that infect marine organisms other than diatoms.
The conclusion attributes the quadrupled ratio of viral DNA fragments to diatom microfossils specifically to an intensified rate of viral infection among diatoms. For this inference to hold, the viral DNA must represent infections occurring within diatoms rather than other marine taxa that leave no mineralized fossils. Negating this statement establishes that the viral DNA predominantly came from viruses infecting non-diatom organisms, which completely severs the link between the sediment ratio and diatom viral infections.

Adım Adım Çözüm

1
Analyze the argument's structure and identify premises and conclusion
Premise 1: Dust-rich epochs feature a fourfold increase in the ratio of giant virus DNA fragments to diatom microfossils in sediment cores. Premise 2: Atmospheric dust delivers bioavailable iron that accelerates diatom reproduction. Conclusion: Iron enrichment intensifies the rate of viral infection among diatoms.
Deconstructing the argument isolates the logical leap between sediment fossil ratios and diatom-specific infection rates.
2
Identify the unstated gap (Defender Assumption)
The researcher assumes that the viral DNA found in the sediment actually corresponds to infections of diatoms, rather than infections of other co-occurring marine organisms whose populations or viral dynamics also responded to dust.
If the viral DNA comes from non-diatom hosts, the ratio of viral DNA to diatom frustules in the sediment cannot prove that diatoms experienced higher viral infection rates.
3
Apply the Negation Test to confirm necessity
Negating the correct statement gives: 'The giant virus DNA fragments detected in the sediment cores DID predominantly originate from viruses that infect marine organisms other than diatoms.' This directly invalidates the inference about diatom infection rates.
A necessary assumption must fatally undermine the conclusion when logically negated.

Anahtar Kavram

Necessary Assumption (Defender Assumption and Negation Test)
Tahmini Süre:1m 30s
Soru 35Soru →

Public Health Official: The new occupational safety regulations implemented at the Apex Manufacturing plant have clearly been successful in making the facility a safer place to work. Despite the plant increasing its total manufacturing output by 30 percent this year, the annual number of reported workplace injuries has remained exactly the same as last year before the regulations took effect.

Statement: The public health official's argument depends on the assumption that the plant did not achieve its increase in output by heavily automating its processes and significantly reducing the size of its human workforce.

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Cevap: True

Cevap

True
The proposed statement identifies a necessary 'defender' assumption. The argument relies on a flat absolute number (total injuries) to support a claim about a rate (workplace safety). For 'same total injuries' to mean 'safer', the underlying population of workers must not have significantly decreased. If the plant achieved its output by drastically cutting its human workforce through automation, then the same number of injuries occurred among far fewer workers, meaning the injury rate per worker skyrocketed. Because the argument completely collapses if we assume a severe workforce reduction occurred, the argument must implicitly assume that such a reduction did not occur.

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1
Identify the conclusion and premises of the public health official's argument.
Conclusion: The new safety regulations made the facility a safer place to work. Premises: Manufacturing output increased by 30%, but the total number of reported injuries remained exactly the same.
Deconstructing the argument is necessary to expose the logical gap between the evidence and the claim.
2
Analyze the logical gap between the premises and the conclusion.
The argument uses an absolute number (total injuries) to make a claim about safety (a rate of risk per individual worker). For the conclusion to hold, the author must assume the total number of workers exposed to risk did not significantly decrease.
If the number of workers decreased while total injuries stayed the same, the risk per worker actually increased.
3
Apply the Negation Test to the proposed assumption.
Negated statement: The plant DID achieve its increase in output by heavily automating its processes and significantly reducing the size of its human workforce.
The Negation Test is the definitive LSAT method for proving whether an assumption is logically necessary.
4
Evaluate the impact of the negated statement on the argument.
If the plant significantly reduced its workforce, the constant number of total injuries means the injury rate per remaining worker increased drastically. This destroys the conclusion that the facility is a safer place to work.
Because negating the statement invalidates the argument's conclusion, the statement must be a necessary assumption.

Anahtar Kavram

Defender Assumptions and the Numbers vs. Rates Flaw
Soru 36Soru →

Chronobiologist: A recent two-year study monitored adolescent students who completed their academic assignments during early morning hours rather than late evening hours. These morning-studying students reported substantially higher sleep quality and improved memory retention. Therefore, shifting mentally demanding tasks from late evening to early morning directly optimizes sleep architecture and cognitive performance in adolescents.

Which of the following statements, if true, most seriously weaken the chronobiologist's argument? (Select all that apply)

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Cevap: Students who voluntarily shifted their study schedule to the morning already adhered to stricter household limits on evening screen exposure, an independent factor known to improve adolescent sleep quality.; Adolescents with naturally advanced circadian rhythms, who inherently experience superior sleep consolidation and baseline memory retention, are disproportionately more likely to adopt morning study routines.

Cevap

The statements establishing an alternative confounding cause (household screen time limits) and a self-selection bias based on preexisting biological chronotypes both weaken the argument by undermining the author's direct causal conclusion.
The conclusion asserts a direct causal relationship based purely on a correlation observed between study timing and sleep/memory metrics. The statement showing that morning studiers were subject to stricter evening screen time limits provides an alternative causal explanation for the improved sleep. Similarly, the statement showing that students with naturally advanced circadian rhythms already possess superior sleep consolidation demonstrates that baseline biological differences, rather than the schedule change itself, likely account for the observed benefits.

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1
Identify the conclusion and underlying premises in the argument.
Premise: Morning-studying adolescents had better sleep quality and memory scores than evening studiers. Conclusion: Shifting mentally demanding tasks to the morning directly causes optimized sleep architecture and cognitive retention.
Weaken questions require targeting the unstated logical gap between the correlation observed in the premise and the causal link asserted in the conclusion.
2
Formulate potential vulnerabilities in the causal inference.
The author assumes no confounding third variables (such as other lifestyle habits) and no self-selection bias (inherent physiological differences between morning and evening types) explain the observed correlation.
Causal claims based on observational studies are inherently vulnerable to alternate causes, reverse causality, and selection bias.
3
Evaluate each choice against the causal gap.
The option citing stricter household screen limits introduces a plausible confounding variable, and the option noting inherent circadian advantages explains the correlation via selection bias. Both undermine the conclusion.
Introducing credible alternative explanations directly breaks the necessary assumption that the homework timing itself caused the beneficial outcomes.

Anahtar Kavram

Alternative Causal Explanations and Selection Bias
Tahmini Süre:1m 30s
Soru 37Soru →

Match each paradoxical operational scenario with the underlying causal fact that most effectively resolves its apparent discrepancy.

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Öğeler

A municipal water district mandated high-efficiency low-flow plumbing fixtures, resulting in a 25 percent reduction in total residential water consumption, yet the average household monthly water bill rose significantly.
An agricultural cooperative converted arid crop fields from flood irrigation to high-efficiency subsurface drip irrigation, yet the concentration of mineral salts in the upper root zone increased substantially.
A corporation implemented frequent unannounced simulated phishing tests with punitive retraining for failures, yet the actual reporting rate of genuine malicious emails sent to security staff dropped by half.

Eşleşmeler

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Cevap

Match the water tariff scenario with fixed infrastructure cost redistribution; match the subsurface irrigation salinity scenario with the failure of low-volume water to leach salts below the root zone; match the phishing drill scenario with penalty aversion causing employee disengagement.
Each correct pairing provides an auxiliary causal factor that simultaneously accounts for the implementation of the measure and explains why the counterintuitive secondary effect occurred without disputing the initial premises.

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1
Identify the two mutually conflicting facts in each scenario
Identified consumption drop vs. bill increase, water efficiency gain vs. soil salinity increase, and increased training frequency vs. decreased real-world incident reporting.
Resolving a paradox requires clarifying the precise tension between the observed intervention and the unexpected outcome.
2
Evaluate candidate causal mechanisms to see which bridges both facts without contradicting either premise
Fixed cost reallocation bridges water volume and billing; lack of soil leaching bridges low-volume delivery and mineral buildup; employee risk aversion bridges punitive drills and lower voluntary reporting.
An effective resolution must allow both stated premises to remain true while supplying an unstated mechanism that produces the surprising result.
3
Verify that no matched mechanism denies the premises or addresses an irrelevant external factor
Each pair establishes a direct, logically sound causal link explaining the observed discrepancy.
Ensures full compliance with logical reasoning standards.

Anahtar Kavram

Resolving Discrepancies via Unaccounted Intervening Mechanisms
Tahmini Süre:1m 30s
Soru 38Soru →

Match each short argument on the left with the evidentiary finding on the right that most effectively strengthens its central conclusion.

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Öğeler

Archaeologists excavating pre-Columbian earthworks in the Llanos de Moxos noted that plots enriched with charcoal-based terra preta supported continuous maize cultivation for centuries without nutrient exhaustion. Researchers concluded that the deliberate addition of charcoal compost was the primary factor preventing tropical soil leaching in these fields.
Zoologists observed that European robins in metropolitan areas sing at higher frequencies than their rural counterparts. Because city traffic produces loud, low-frequency sound, the researchers concluded that this vocal frequency adjustment is an active behavioral adaptation to prevent traffic noise from masking territorial signals.
During seventeenth-century Sweden's copper-standard era, commodity prices surged each time the central treasury issued heavy copper plate currency. Economic historians concluded that the domestic price inflation was directly driven by the expansion of the circulating copper money supply rather than by concurrent wartime shipping blockades.

Eşleşmeler

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Cevap

Argument 1 (charcoal soil fertility) matches with the control plot finding showing non-charcoal plots suffered leaching; Argument 2 (urban robin vocal frequency) matches with the sound-chamber experiment demonstrating frequency-specific pitch elevation; Argument 3 (Swedish copper inflation) matches with the inland provincial data showing inflation independent of trade blockades.
Each correct match pairs an argument with an empirical finding that eliminates a major competing explanation: the agricultural match uses a negative control to prove charcoal's unique role; the ornithology match uses frequency-selective testing to confirm adaptive signal design; and the economic match uses an insulated market subset to rule out wartime blockades.

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1
Analyze the core conclusion and potential causal gap in the agricultural argument.
The argument concludes that charcoal compost prevented nutrient leaching, assuming other farming techniques or environmental factors were not solely responsible.
Strengthening this requires an effective control comparison demonstrating that the charcoal element was the decisive factor in preventing soil exhaustion.
2
Analyze the urban ornithology argument regarding noise masking.
The argument concludes that robins actively shift pitch to counter low-frequency traffic masking, assuming the shift is not a generalized physiological stress reaction to overall noise volume.
Strengthening this requires evidence showing the behavioral response is specifically calibrated to low frequencies rather than all auditory disturbances.
3
Analyze the economic history argument attributing price surges to currency expansion.
The argument asserts copper issuance caused inflation while dismissing trade blockades as the primary cause.
Strengthening this requires ruling out trade blockades by showing currency expansion generated inflation even in isolated regions immune to blockade effects.

Anahtar Kavram

Evaluating evidentiary support by establishing control comparisons, demonstrating frequency specificity, and eliminating confounding causal variables.
Tahmini Süre:2m 0s
Soru 39Soru →

Each passage below presents an academic argument that relies on an unstated foundational premise. Match each numbered argument with the underlying assumption on which it strictly depends.

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Öğeler

Astronomer: Atmospheric spectroscopy of the temperate rocky exoplanet Proxima-b reveals trace concentrations of phosphine. On Earth, phosphine gas is produced almost exclusively by anaerobic microbial metabolism. Therefore, the presence of phosphine on Proxima-b constitutes strong evidence for the existence of extraterrestrial life.
Historical Linguist: Discovered clay tablets from the ancient trade city of Kanesh transcribe both high and mid front vowels using the same cuneiform character. Because all known spoken languages maintain phonemic distinctions between these vowel heights to avoid rampant homophony, the scribes at Kanesh must have spoken a vernacular dialect that differed markedly from the literary language of the region.
Economist: Over the last decade, domestic manufacturing firms that invested heavily in automated robotic assembly increased their payrolls by an average of fifteen percent. Consequently, the adoption of industrial robotics across the manufacturing sector does not result in an overall reduction of manufacturing employment.

Eşleşmeler

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Cevap

Argument 1 matches the assumption that abiotic geochemical or photolytic processes cannot generate stable atmospheric phosphine; Argument 2 matches the assumption that the written tablets were intended to phonetically reflect spoken dialect; Argument 3 matches the assumption that hiring gains in automating firms did not displace a greater number of workers in competing firms.
Each pair correctly matches an argument to an unstated premise that is strictly necessary for its conclusion to follow. In each case, negating the matched assumption destroys the logic: if phosphine can form abiotically, the presence of phosphine is not evidence of life; if scribal conventions do not reflect spoken phonetics, orthographic omission is not evidence of a dialect split; and if automating firms displace competitor jobs, firm-level hiring is not evidence of sector-wide net job preservation.

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1
Isolate the conclusion and premise of each argument to identify the inferential gap.
Argument 1 jumps from terrestrial biological phosphine production to exoplanetary life; Argument 2 jumps from written orthography to spoken dialect; Argument 3 jumps from firm-level hiring to sector-wide aggregate employment.
Necessary assumptions must bridge the conceptual leap between the stated premises and the stated conclusion.
2
Formulate the essential condition required for each conclusion to hold validly.
Argument 1 requires ruling out non-biological phosphine sources; Argument 2 requires that the writing system reflects spoken phonology; Argument 3 requires that firm-level job gains were not offset by competitor job losses.
Applying the Negation Test reveals that denying any of these foundational claims completely invalidates its corresponding conclusion.
3
Match each argument to its corresponding required underlying premise.
Each argument maps directly to its unique foundational requirement without ambiguity.
Confirming one-to-one logical necessity ensures accurate pairing across all three arguments.

Anahtar Kavram

Necessary Assumption (Negation Test)
Tahmini Süre:2m 0s
Soru 40Soru →

Legal Scholar: A statute cannot be considered legitimately authoritative unless it reflects the deeply held moral convictions of the populace it governs. Reflecting such convictions necessitates that the legislative body drafting the statute be completely insulated from the financial influence of special interest groups. The recently enacted Corporate Accountability Act was drafted by a committee heavily financed by the very industries it seeks to regulate. Therefore, the Act will inevitably face widespread civil disobedience.

Which one of the following, if assumed, enables the legal scholar's conclusion to be properly drawn?

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Cevap: No statute can avoid facing widespread civil disobedience unless it is legitimately authoritative.

Cevap

The correct answer is the statement indicating that no statute can avoid facing widespread civil disobedience unless it is legitimately authoritative.
The argument's premises establish a conditional chain: if a statute is legitimately authoritative, it must reflect moral convictions, which in turn requires insulation from financial influence. Because the Corporate Accountability Act was drafted by a financially influenced committee, it fails the necessary condition for insulation. By applying the contrapositive, the Act cannot be legitimately authoritative. The conclusion then abruptly claims the Act will face widespread civil disobedience. To logically guarantee this conclusion, we need an assumption bridging the gap: if a statute is not legitimately authoritative, it will face civil disobedience. The correct option provides exactly this bridge using 'unless' conditional phrasing: 'cannot avoid civil disobedience' unless 'legitimately authoritative' translates to 'If it is not legitimately authoritative, it will face civil disobedience'.

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1
Map the conditional statements in the premises.
Legitimately Authoritative (LA) → Reflects Moral Convictions (RMC) → Insulated from Financial Influence (IFI).
To understand the chain of necessary conditions established by the legal scholar.
2
Apply the factual premise to the conditional chain.
The Corporate Accountability Act (CAA) was drafted by a heavily financed committee, meaning it is not insulated (~IFI). By contrapositive (~IFI → ~RMC → ~LA), the CAA is not legitimately authoritative (~LA).
To determine what can be proven about the Corporate Accountability Act using only the provided evidence.
3
Identify the logical gap between the inferred evidence and the main conclusion.
We have proven the CAA is not legitimately authoritative (~LA). The conclusion claims the CAA will face widespread civil disobedience (WCD). The gap is: ~LA → WCD.
A sufficient assumption must completely bridge the gap between what is proven and what is concluded.
4
Evaluate the options to find the one that establishes the necessary conditional bridge (~LA → WCD).
The phrase 'No statute can avoid WCD unless LA' translates logically to 'If ~LA, then WCD'. This matches the gap perfectly.
To ensure the selected option provides 100% deductive certainty for the conclusion.

Anahtar Kavram

Sufficient Assumption in Conditional Logic Chains
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