A alone can do a work in 30 days. He did half of the work and then left. If B alone can do the entire work in 16 days, then how many days will B take to complete the remaining work?

9 12 6 8

8

A = 30 days, B = 16 days, ⇒ A completed half of the work = 240 - 120 = 120 units, ⇒ Time taken by B to complete remaining work = \(\frac{120}{15}\) = 8 days,   ..(\(\frac{Work}{Efficiency}\) = Time)