Question

if 20 men can build a 112m long wall in 6 days. what will be the length of a similar wall that can be built by 25 men in 3 days.

Answer 1

in 6 days 20 men can build 112m long wall
in 1 day 20 men can build 112÷6m long wall
in 1 day 1 men can build 112÷6÷20m long wall
in 3 days 25 men can build 112÷6÷20×3×25m long wall=80m

Answer 2

Given :

20 men can build a 112m long wall in 6 days.

To Find :

what will be the length of a similar wall that can be built by 25 men in 3 days.

Solution:

Length of wall built by 20 men in 6 days = 112 m

Length of wall built by 1 man in 6 days = $\frac{112}{20}$

Length of wall built by 1 man in 1 day = $\frac{112}{20 \times 6}$

Length of wall built by 25 men in 1 day = $\frac{112}{20 \times 6} \times 25$

Length of wall built by 25 men in 3 days = $\frac{112}{20 \times 6} \times 25 \times 3 = 70 m$

Hence the length of a similar wall that can be built by 25 men in 3 days is 70 m