# A certain work in 60 If one man works equal to 2 boys :

12 men and 18 boys working 7 1/2 hours a day can do a certain work in 60 If one man works equal to 2 boys, then the number of boys required to help 21 men to do twice the work in 50 days, working 9 hours a day, will be

- 30
- 42
- 48
- 90

**Answer: (2) 42 **

**Explanation:-**

Let required number of boys = X

1 man = 2 boys

(12 men + 18 boys)

(12 x 2 + 18) boys = 42 boys

21 men + X boys a (21 x 2 + X) boys = (42+X) boys

[50 X 9 X 1 X (42 + x)] = (60 X X 2 X 42)

(42 + X) = (37800/450)

= 42 + X = 84

=> X = 42.

Hence, the correct answer is option (2) 42.