Verbal — Critical Reasoning for the GMAT Exam

Common failure modes

These are the patterns that cause most candidates to lose marks on this topic. Recognising them in advance is half the work.

• !Selecting an answer that is relevant to the topic but does not affect the specific argument in the stimulus
• !Confusing "weakens the argument" with "contradicts the conclusion"
• !Treating assumptions as conclusions — missing the unstated premise that the argument requires

Study tips

• 1Identify the conclusion first, then the evidence, then the gap (assumption) before reading answer choices.
• 2For Weaken questions, the correct answer attacks the assumption, not just the evidence or conclusion in isolation.
• 3Eliminate answer choices that are "out of scope" — they introduce topics the argument never discusses.

Sample GMAT Verbal — Critical Reasoning questions

These sample items mirror the format and difficulty of real GMAT questions. Practice with thousands more on the free Koydo question bank.

1. 1

   Argument: "Our city installed speed cameras on Main Street, and traffic fatalities on that street fell by 30% in the following year. Therefore, speed cameras reduce traffic fatalities." Which of the following, if true, most weakens this argument?

   • AOther cities without speed cameras also saw fatality reductions that year
   • BSpeed cameras generate significant revenue for the city
   • CMain Street underwent major road resurfacing before the cameras were installedCorrect
   • DThe cameras have not been tested on rural roads
   Why this answer?

   The argument assumes the cameras caused the fatality reduction. If Main Street was resurfaced before camera installation, the resurfacing (not the cameras) could explain the reduction — this weakens the causal claim. Option A would weaken but is less direct; options B and D are out of scope.

2. 2

   A "necessary assumption" question asks you to find the assumption WITHOUT WHICH:

   • AThe conclusion becomes stronger
   • BThe argument falls apart (the conclusion cannot be drawn)Correct
   • CThe evidence is irrelevant
   • DThe argument becomes circular
   Why this answer?

   A necessary assumption is one the argument must take for granted; if it is false, the argument collapses. Test it with the Negation Test: negate the candidate assumption and check if the argument becomes invalid.