Model 2  Filling tank by parts or fractions Section-Wise Topic Notes With Detailed Explanation And Example Questions

Question : 1

A tap can fill an empty tank in 12 hours and another tap can empty half the tank in 10 hours. It both the taps are opened simultaneously, how long would it take for the empty tank to be filled to half its capacity ?

a) 15 hours

b) 30 hours

c) 12 hours

d) 20 hours

Question : 2

A cistern has two pipes. One can fill it with water in 8 hours and other can empty it in 5 hours. In how many hours will the cistern be emptied if both the pipes are opened together when $3/4$ of the cistern is already full of water ?

a) 6 hours

b) 13$1/3$ hours

c) 3$1/3$ hours

d) 10 hours

Question : 3

Three pipes A, B and C can fill a tank in 6 hours, 9 hours and 12 hours respectively. B and C are opened for half an hour, then A is also opened. The time taken by the three pipes together to fill the remaining part of the tank is

a) 2$1/2$ hours

b) 3 hours

c) 3$1/2$ hours

d) 2 hours

Question : 4

$3/4$ part of a tank is full of water. When 30 litres of water is taken out, the tank becomes empty. The capacity of the tank is

a) 40 litres

b) 36 litres

c) 38 litres

d) 42 litres

Question : 5

Pipes P and Q can fill a tank in 10 and 12 hours respectively and C can empty it in 6 hours. If all the three are opened at 7 a.m., at what time will one-fourth of the tank be filled ?

a) 11 p.m.

b) 10 a.m.

c) 11 a.m.

d) 10 p.m.