Question

15 men can build a wall in 60 days. How many more men are required to build another wall of same size in 45 days?

• A. 15 men
• B. 20 men
• C. 5 men
• D. 3 men

Answer 1

The correct option is C

5 men

Greater the number of men building the wall, lesser the time needed for the completion of the task. Hence, this is a case of inverse proportion.
Let $x$ be the number of men needed to complete the work in 45 days

$\therefore$ $\frac{15}{x}$ = $\frac{45}{60}$

$\frac{15}{x}$ = $\frac{3}{4}$

$x$ = $\frac{15\times 4}{3}$

= 20

Since there are 15 men already , so 5 more men are needed to build another wall in 45 days