Question

81.
Two pipes A and B can fill a cistern in 20 minutes and 30 minutes respectively. Both pipes are
opened, but pipe B is closed 5 minutes before the cister is full. How much time is required to fill
the cisten?
(a) 8 minutes
(b) 10 minutes (c) 12 minutes
(d) 14 minutes (c) 16 minutes​

Answer 1

Answer:

is a option (b) 10 minutes