If pipes, A and B, together can fill a tank in 20 minutes and A alone can fill in 30 minutes. Then pipe B alone can fill the tank in :
If pipes, A and B, together can fill a tank in 20 minutes and A alone can fill in 30 minutes. Then pipe B alone can fill the tank in :
[A]51 minutes
[B]60 minutes
[C]61 minutes
[D]62 minutes
60 minutes
Because according to the question, part of the tank filled by pipe B in
$latex 1\ minute\ = \frac{1}{20}-\frac{1}{30}= \frac{3-2}{60}= \frac{1}{60}&s=1$
Hence pipe B alone can fill the tank in 60 minutes, and option [B] is correct answer.