A tap can fill a cistern in 8 hours and another tap can empty it in 16 hours. If both the taps are open, the time (in hours) taken to fill the tank will be:
A tap can fill a cistern in 8 hours and another tap can empty it in 16 hours. If both the taps are open, the time (in hours) taken to fill the tank will be:
[A]24 hours
[B]16 hours
[C]10 hours
[D]8 hours
16 hours
Part of the cistern filled in 1 hour = 1$latex \div$8
Part of the cistern emptied in 1 hour = 1$latex \div$16
When both the taps are opened simultaneously, part of cistern fill in 1 hour = $latex \frac{1}{8}-\frac{1}{16}=\frac{2-1}{16}=\frac{1}{16}&s=1$
Hence, the cisatern wil be filled in 16 hours.
So option [B] is the right answer.