Multiple choice

If 4 examiners can examine a certain number of answer books in 8 days by working 5 hours a day for how many hours a day would 2 examiners have to work in order to examine twice the number of answer books in 20 days?

  1. 5 hours

  2. 6 hours

  3. 8 hours

  4. 10 hours

  5. 12 hours
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Work = Examiners × Days × Hours. Let W = work for original books. 4 × 8 × 5 = 160 examiner-hours. New work is twice: 2W = 320 examiner-hours. With 2 examiners for 20 days: 2 × 20 × h = 320, so 40h = 320, h = 8 hours. Option C is correct.

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