Multiple choice

42 boys can complete a piece of work in 20 days working 8 hours per day. In how many days can 14 boys complete the same work, each boy working 12 hours per day?

  1. 39 days

  2. 40 days

  3. 41 days

  4. 42 days
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Using the work formula: boys × days × hours = constant work. 42 × 20 × 8 = 6720 total work units. For 14 boys working 12 hours daily: 14 × d × 12 = 6720, giving d = 6720/168 = 40 days. Fewer boys working longer hours balances out to the same total time.

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