Question

112 men can build a railway tunnel in 72 days how many more men will be required to build the tunel in 48 days? (unitary method)

Answer 1

In 72 days work will be completed by 112 men,

then
in 1 day work will be completed by 112×72 men,

then
in 48 days work will be completed by (112×72)/48 men =168 men