Critical Reasoning Assumptions and Flaws
This topic covers conclusions, premises, assumptions, flaws, causal arguments, sampling, necessary assumptions, and evaluating argument support.
How to study for the GMAT
Build every answer around the exact decision: problem setup, argument gap, passage support, data source, sufficiency, table filter, graph label, or linked two-part condition.
Core concepts
Concept 1
Critical Reasoning Assumptions and Flaws questions test the reasoning and decision skills used on the current GMAT exam.
Exam cue: Name the task type: problem solving, reading comprehension, critical reasoning, data sufficiency, multi-source reasoning, table analysis, graphics interpretation, or two-part analysis.
Concept 2
The strongest answer identifies the business-relevant task, data source, argument relationship, arithmetic setup, or decision criterion before comparing choices.
Exam cue: Check constraints, units, variables, claim structure, source tabs, table filters, graph axes, and whether the answer is enough to make the decision.
Concept 3
Eliminate choices that answer a different question, overlook a condition, misuse a source, ignore sufficiency, or rely on specialized outside knowledge.
Exam cue: Use review and edit time to verify the exact question, not just the topic that first looked familiar.
Risk pitfalls and guardrails
Solving a nearby math or reading task while missing the decision the item actually asks for.
Guardrail: Use a 15-second safety pause before finalizing your action.
Using outside business knowledge instead of the evidence, data, or argument in the prompt.
Guardrail: Use a 15-second safety pause before finalizing your action.
Ignoring GMAT-specific constraints such as no calculator in Quant and sufficiency rather than calculation in Data Insights.
Guardrail: Use a 15-second safety pause before finalizing your action.
Memory anchors
Conclusion
The conclusion is the argument's main claim.
Premise
A premise is evidence offered for the conclusion.
Necessary Assumption
A necessary assumption must be true for the argument to work.
Flaw
A flaw is a weakness in the reasoning.
Causal Argument
A causal argument claims one thing produces or affects another.
Sampling
Sampling reasoning depends on whether the sample supports the broader conclusion.
Gap
A gap is the missing connection between evidence and conclusion.
Counterexample
A counterexample shows where a general claim may fail.
Relevance
Relevant evidence affects the conclusion rather than a side issue.
Conclusion Scope
Conclusion scope limits what the argument actually tries to prove.
Checkpoint rule
Do the check-up only after you can summarize each concept in one sentence and identify one dangerous pitfall from memory.
Knowledge Check (after reading)
Short check-up to confirm understanding of this module.
Check-up Questions
A café plans to replace paper loyalty cards with a phone app. Managers predict that repeat visits will increase because customers are less likely to lose a phone than a paper card. The prediction depends on which assumption?
A magazine surveyed visitors to its investing website and found that 82 percent trade stocks at least monthly. The magazine concludes that 82 percent of all adults trade stocks at least monthly. What is the principal flaw?
Answer all questions to submit.
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Move forward only after this module is stable.
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