31)

A cistern of capacity 40 litres has an inlet and an outlet pipe. When both the pipes are opened at once, it takes 8 minutes to fill the cistern. However, if the outflow rate is increased 1.5 times, the cistern never gets filled. Which of the following can be the outflow rate?

A)

8 litres/minute

B)

6 litres/minute

C)

10 litres/minute

D)

9 litres/minute

32)

A tank is filled by three pipes with uniform flow. The first two pipes operating simultaneously fill the tank in the same time during which the tank is filled by the third pipe alone. The second pipe fills the tank 5 hours faster than the first pipe and 4 hours slower than the third pipe. The time required by the first pipe is:

A)

6 hours

B)

10 hours

C)

15 hours

D)

30 hours

33)

Three taps A, B and C can fill a tank in 12, 15 and 20 hours respectively. If A is open all the time and B and C are open for one hour each alternately, the tank will be full in:

A)

6 hrs

B)

7 hrs

C)

8 hrs

D)

8 hrs

34)

Two pipes can fill a tank in 10 and 14 minutes respectively. A third pipe can empty the tank at the rate of10 liters/minute. If all the pipes working together can fill the empty tank in 8 minutes, what is the capacity of the tank?

A)

210 liters

B)

215.4 liters

C)

220 liters

D)

225.4 liters

35)

Two pipes A and B individually can fill a tank in 15 hours, and 12 hours respectively, and C can empty the full tank in 4 hour. If all three pipes are open at 8, 9, and 11 am respectively. At what time tank will be completely empty?

A)

2:40 pm

B)

1:00 pm

C)

12:00 pm

D)

1:35 pm