A can finish a piece of work in 48 days and B can finish it in 60 days. They work together for 12 days and then A goes away. In how much time (in days and hours) will B finish 25% of the remaining work?

8 days 6 hours

A = 48 days, B = 60 days.

⇒ They both worked together for 12 days, i.e;

 (5 + 4) x 12 = 108 units of work.              ..(Efficiency × Days = Total work)

⇒ Remaining work = 240 - 108 = 132 units.

⇒ Time taken by B  to complete 25% of the remaining work 

= 25% of 132 = 33 units = \(\frac{33}{4}\) = \( { 8}_{4 }^{ 1} \) days.

which can be written as 8 days and 6 hours.