Multiple choice

Four examiners can examine a certain number of answer papers in 10 days by working for 5 hours a day. For how many hours in a day would 2 examiners have to work in order to examine twice the number of answer papers in 20 days?

  1. 10 hours

  2. 8 hours

  3. 7 hours

  4. 6 hours

  5. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Work = 4 examiners × 10 days × 5 hours = 200 examiner-hours. For twice the work (400 units) by 2 examiners in 20 days: 400 = 2 × 20 × h. So h = 400 / 40 = 10 hours per day (option A). This uses inverse proportion: fewer examiners means more hours needed.

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