Multiple choice

28 men can do a piece of work in 12 days. How many men would be required to do the same work in 21 days?

  1. 12 days

  2. 14 days

  3. 16 days

  4. 18 days

  5. 24 days
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is an inverse variation problem: more days means fewer men. Use the formula M1 × D1 = M2 × D2. So 28 × 12 = M2 × 21, which gives M2 = (28 × 12) / 21 = 336 / 21 = 16 men. The work is constant, so men and days are inversely proportional.

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