Question

40 men can do a piece of work in a given time. If only 30 men be engaged, 6 more days are needed to complete the work. In how many days can 60 men do the work ? 

(a) 9 

(b) 10 

(c) 12 

(d) 15

Answer 1

(c) 12

Suppose 40 men can do a piece of work in x days. Then,

30 men can do the same work in \(\frac{X\times40}{30}\) days = (x + 6) days

\(\Rightarrow\) 4x = 3x + 18 \(\Rightarrow\) x = 18

\(\therefore\) 60 men can do the same work in \(\frac{18\times40}{60}\) days = 12 days.