Question

If 25 men working 8 hours a day can do a piece of work in 18 days.In how many days 18 men working 10 hours a day will finish double the work??

Answer 1

25 men working 8 hours a day finish the work in 18 days.

So total time =18×8=144hrs = 6 days

That means 25 men finish a work in 6 days.

So 25 men in one day will finish

$= \frac{1}{6} \: parts$

So one man can finish the same work in one day

$= \frac{1}{6 \times 24} = \frac{1}{144} \: parts$

So 18 men will finish in one day

$= 18 \times \frac{1}{144} = \frac{1}{8} \: parts$

So total time taken by them

$= 8 \: days \: = 192 \: hours$

They work 10 hours a day.

So number of days required

$= \frac{192}{10} = 19.2 \: days \: (1 \: time)$

Twice of work need twice time = 19.2×2= 38.4 days=38 days 6 hrs