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GMAT Review: Problem Solving

Review problem solving for this GMAT question with the key prompt clue, correct-answer reasoning, distractor checks, and sources to verify next.

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This question-specific review guide is tied to the answer reasoning for a PracticeTestVault item. Use it after you answer the question so the review stays focused on what the prompt actually tested.

What this question is testing

Objective: Problem Solving

Prompt focus: A store sells notebooks for 3 dollars each. If a customer buys 12 or more notebooks, the price drops to 2.50 dollars each for all notebooks purchased. How much does a customer pay for 15 notebooks?

Why the correct answer works

37.50 dollars

Buying 15 notebooks qualifies for the 2.50 dollar price, so 15 times 2.50 is 37.50 dollars.

Why the tempting wrong answer fails

This uses the full 3 dollar price, ignoring the bulk discount that applies at 12 or more.

Plain-language takeaway

Since 15 is at least 12, every notebook costs 2.50 dollars. The total is 15 times 2.50, which equals 37.50 dollars.

Simple analogy

Think of problem solving like following a short checklist: identify the clue, confirm the rule, and then make the move that fits this exact scenario.

How to review it before a retake

  • Underline the command word and name what the question is asking before rereading the choices.
  • Compare the correct answer against the closest distractor and write the exact detail that separates them.
  • Retest this objective with a fresh question without looking at the rationale first.

Sources to verify next