Multiple choice

20 Men can do a work in 30 days. Then find after how many days 5 men should stop the work so that work will be completed in 35 days?

  1. 10

  2. 15

  3. 12

  4. 8

  5. 20

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Total work = 20 men × 30 days = 600 man-days. Let x be the days after which 5 men leave. For first x days: 20 men work, contributing 20x man-days. For remaining (35-x) days: 15 men work, contributing 15(35-x) man-days. Total: 20x + 15(35-x) = 600. Solving: 20x + 525 - 15x = 600, so 5x = 75, and x = 15 days. Option B is correct.