20 men could complete a work in 80 days. They worked together for 60 days, after that due to bad weather the work is stopped for 10 days. How many more men should be employed so as to complete the work in time?
D
Correct answer
Explanation
In 60 days, 20 men complete 60/80 = 3/4 of the work. Remaining 1/4 work must be done in 10 days by adding m men. Work rate equation: (20+m) × 10 = (1/4) × 20 × 80 = 400 man-days. Solving: 200 + 10m = 400, giving m = 20. So 20 additional men are needed to complete the remaining work in the stipulated time.