Pipes and Cisterns Practice Test 1 with solutions

Part of cistern filled by A and B in 2 minutes
=

1

8

+

1

12

=

5

24

Part of cistern filled by A and B in 8 minutes
=

5

24

×4 =

20

24

Part of tank remaining empty = 1−

20

24

=

4

24

=

1

6

Part of tank remaining empty after 9 minutes
=

1

6

−

1

8

=

4−3

24

=

1

24

Time taken by Pipe B to fill the tank = 12 minutes
Time taken to fill

1

24

th part of the tank =
12×

1

24

=

1

2

minute
So, total time taken to fill the tank = 9

1

2

minutes.