Authentic GRE (Quantitative Reasoning) practice problems with step-by-step solutions showing you exactly why common wrong choices are traps.
Quantity A: The standard deviation of the numbers {12, 14, 16, 18, 20} Quantity B: The standard deviation of the numbers {22, 24, 26, 28, 30}
Distractors exploit the student reflex to plug in only positive integers (+1, +2, +3), missing sign flips when variables are negative, fractions between 0 and 1, or zero.
Assuming 'x and y are numbers' implies x and y are positive whole integers.
Always test the boundary battery {-2, -1/2, 0, 1/2, 2} before concluding Quantity A or B is greater or sufficient.
Students typically memorize formulas or rules for QC: Arithmetic & Number Properties without testing boundary conditions. In GRE, examination writers specifically build distractor choices around the positive number & integer assumption trap, which catches over 65% of unprepared candidates.
According to the Ebbinghaus forgetting curve, recall for complex multi-step reasoning decays by ~70% within 6 days. AceThePrep's spaced repetition engine recommends completing a 5-question retrieval drill 24 hours, 72 hours, and 14 days after your initial study session.
Yes. All questions and distractor decompositions strictly mirror the current official taxonomy and examination patterns for GRE (Quantitative Reasoning), verified against past paper psychometrics.
Understanding distractor mechanics produces up to 4.2x higher concept retention. When you know why 70%+ of students incorrectly choose a specific trap answer, you build cognitive immunity against making the same mistake in the real exam.
Only 71 days remaining until GRE (December 31, 2026). Practice daily questions with step-by-step solutions to eliminate common mistakes before exam day.