18 boys can complete the work in 24 days. ⇒ Total work = 18×24=432 MD (mandays) Now, 6 boys leave after working for 12 days, ⇒ Work done in these 12 days = 18×12=216 MD Remaining work = 432−216=216 MD After 6 boys left, work done per day will be MD ⇒ Time taken =