Question

If 20 men take 15 days to complete a certain amount of work working at 10 hours per day, then how many more men are required to complete twice the previous work in 10 days working at 12 hours a day?
A. 10
B. 20
C. 30
D. 40

Answer 1

Correct Answer - C
Let the required number of men be x.
We have, `(M_(1)D_(1)H_(1))/W_(1) = (M_(2)D_(2)H_(2))/W_(2)`
`((20)(15)(10))/1 = ((20+x)(10)(12))/2`
` rArr 20 + x = 50 rArr x = 30`.