Question

If 15 men or 24 women or 36 boys can do a piece of work in 12 days, working 8 hours a day, how many men must be associated with 12 women and 6 boys to do another piece of work 2.25 times in 30 days working 6 hours in a day?

• A. 9
• B. 7
• C. 5
• D. 8
• E. 6

Answer 1

The correct option is D

8

Man: Woman: Boys = 15 : 24 : 36 = 5 : 8 : 12

8 women = 12 boys $\Rightarrow$ 12 women = $\frac{12}{8}\times 8=\frac{15}{2}$ men (all converted to men)

12 boys = 5 men 6 boys = $\frac{5}{2}$ men

12 women + 6 boys =$\frac{15}{2}+\frac{5}{2}$ = 10 men.

Let no. of men = ‘x’

Using chain rule, $(x+10)\times 30\times 6=15\times 12\times 8\times 2.25$

x = 8