If $32$ men can reap a field in $15$ days, then in how many days can $20$ men reap the same filed ?

The correct option is C (24 days)

Given $32$ men can reap a field in $15$ days
Let the number of days taken by $20$ men's be $x$
Since, the number of men doing a work and the number of days taken are inverse proportion.
$\Rightarrow 32:20=x:15$
$\Rightarrow \frac{32}{20}=\frac{x}{15}$
$\Rightarrow x=\frac{32\times 15}{20}$
$\therefore x=24$days