Question

Twelve men can complete a work in $8$ days. Three days after they started the work, $3$ more men joined them. In how, many days will all of them together complete the remaining work?

Answer 1

1 man's 1day's work $=\frac{1}{96}$

12 man's 3 day's work $=3\times \frac{1}{8}=\frac{3}{8}$

Remaining work = $\frac{1-3}{8}=\frac{5}{8}$

15 man's 1 day's work = $\frac{15}{96}$

Now, $\frac{15}{96}$ work is done by them in 1 day.

$\therefore \frac{5}{8}$ work will be done by them

in $\frac{96}{15}\times \frac{5}{8}$

$\Rightarrow 4$ days.