How to Review Incorrect Questions So You Do Not Repeat Them

The short answer: for each wrong, guessed or slow question, answer four questions: what did I do, why was it wrong, what is the fix and when will I retest. Without the last one, review feels productive and changes little.

What counts as a question to review

• Wrong answers.
• Guessed answers, including those you got right: they are luck, not knowledge.
• Slow correct answers, where you took more than your ceiling.
• Skipped questions that you could have solved.

Skip questions you solved quickly and confidently. Review time is limited; spend it where marks are.

The four questions

1. What did I do? Write down your thinking in a line: "Assumed the percentage base was the new value."
2. Why was it wrong? Assign a cause: concept gap, formula or fact not remembered, misreading, calculation slip, time pressure or bad guess.
3. What is the fix? A specific action: "Percentage change always uses the old value as the base; revise the page; do 10 questions."
4. When will I retest? A date within a week, and the question or type you will use.

A worked example

Question: A shopkeeper marks an article 25% above cost and gives a 20% discount. What is the profit percentage? Options: 0%, 5%, 10%, 15%. A candidate chose 5% (25 − 20).

1. What did I do? Subtracted the discount percentage from the markup percentage.
2. Why was it wrong? Concept gap: the discount applies to the marked price, not to the cost, so the percentages cannot be subtracted.
3. What is the fix? Use multiplying factors: selling price = cost × 1.25 × 0.80 = cost × 1.00. Profit is 0%. Revise the page on successive percentage changes; do 10 markup-and-discount questions.
4. When will I retest? Three days from now: five similar questions without notes.

The correct answer is 0%, since 1.25 × 0.8 = 1. Notice that the cause is conceptual, so the fix is a rule plus practice, not "be more careful".

Match the fix to the cause

A time budget

For a 100-question mock where you review 25 questions, allow about 90 minutes: 10 minutes for numbers and cause counts, 50 minutes for the four questions across 25 items (two minutes each), 20 minutes to repair the top topic and 10 minutes to schedule retests. If you have less time, reduce the number of questions reviewed but keep all four questions for each.

What to do with the results

• Count errors by cause and by topic; the biggest counts are your next study targets.
• Put the repeated ones in your error log.
• Follow with a 48-hour repair: see how to revise after a mock test.

Review the right answers too

For questions you got right by a long route, check whether there is a faster method. For questions you got right by guessing, treat them as wrong. For those that took long, ask: could a ceiling have saved time?

Common mistakes

• Reading the solution and nodding. Understanding a solution is not the same as being able to produce it.
• Labelling everything "silly mistake". Often a concept gap is hiding there.
• Never retesting.
• Reviewing everything, which makes review too long to sustain.
• Not writing the fix.

Try the method on your next practice test.