A and B together can do a piece of work in 10 days. A alone can do it in 30 days. The time in which B alone can do it is :
A and B together can do a piece of work in 10 days. A alone can do it in 30 days. The time in which B alone can do it is :
[A]10
[B]12
[C]20
[D]15
15
(A+B)’s 1 day’s work = $latex \frac{1}{10}&s=1$
A’s 1 day’s work = $latex \frac{1}{30}&s=1$
∴ B’s 1 day’s work = $latex \frac{1}{10}-\frac{1}{30}&s=1$
=$latex \frac{3-1}{30}=\frac{2}{30}=\frac{1}{15}&s=1$
Hence, B, alone can complete the work in 15 days.