Question

A contractor has to finish a work in 20 days and employs 30 men on the job. If the
work is to be finished in 15 days, the number
of extramen to be employed is. ​

Answer 1

Answer:

In $20$days men are needed $30$.

So,to finish the work in $1$day men needed $30\times 20$.

Then, to finish the work in $15$ days men needed $\frac{30\times 20}{15}$

$\therefore{40\:men\:are\:needed}$