Aptitude Test Preparation
Aptitude - Home
Aptitude - Overview
Quantitative Aptitude

Aptitude - Pipes & Cisterns Online Quiz

Following quiz provides Multiple Choice Questions (MCQs) related to Pipes & Cisterns. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using Show Answer button. You can use Next Quiz button to check new set of questions in the quiz.

Q 1 - Two funnels can fill a tank in 20 minutes and 30 minutes separately. On the off chance that both the channels are opened at the same time, then the tank will be filled in:

Answer : B

Explanation

Part filled by both pipes in 1 min. =(1/20+ 1/30)= 5/60  = 1/12
Time taken to fill the tank = 12 minutes

Q 2 - A pump can fill a tank with water in 2 hours. In light of a break in the tank, it takes 7/3 hours to fill the tank. The hole can discharge the filled tank in:

Answer : D

Explanation

Part filled by the pump in 1 hr = 1/2
Net part filled by the pump and leak in 1 hr = 3/7
Emptying work done by the leak in 1 hr= (1/2 - 3/7)= 1/14
Leak can empty the tank in 14 hours.

Q 3 - A funnel can discharge a tank in 40 minutes. A second pipe with distance across twice as much as that of the first is likewise joined with the tank to purge it. The two together can exhaust the tank in:

Answer : B

Explanation

A pipe with double diameter will take half time.
So, the second pipe can empty the full tank in 20 min.
Part emptied by both in 1 min. (1/40+ 1/20) = 3/40
Time taken to empty the full tank = 40/3 min.

Q 4 - Two channels can fill a tank in 15 hours and 12 hours separately and a third pipe can purge it in 4 hours. In the event that the channels are opened all together at 8 am, 9 am and 11am separately, the tank will be exhausted at

Answer : D

Explanation

Let the tank be emptied in x hrs after 8 am.
Work done by A in x hrs, by B in (x-1) hrs and C in (x-3) hrs = 0
⇒x/15+ (x-1)/12- (x-3)/4 = 0 ⇒ 4x+5(x-1) - 15(x-3) = 0
⇒6x= 40 ⇒x= 20/3 hrs.
⇒x= 6 hrs. 40 min after 8 am
Hence the tank will be emptied at 14 hrs 40 min, i.e., 2:40 pm

Q 5 - A tank is fitted with two taps A and B. A can fill the tank totally in 45 minutes and B can purge the full tank in 60 minutes. On the off chance that both the taps are opened on the other hand for 1 minute, then in what amount of time the unfilled tank will be filled totally?

Answer : D

Explanation

Work done by A in 1st minutes and B 2nd minute= (1/45- 1/60)= 1/180
Part filled in 2 min = 1/180
Part filled in 358 min = (1/360*358) =   358/360 = 179/180
Remaining part = (1-179/180) = 1/180
1/45 part is filled by A in (45*1/180) min= 1/4 min.
Total time taken to fill it = 358 1/4 min = 5 hrs.58 min 15 sec.

Q 6 - A substantial tanker can be filled by two pipes A and B in an hour and 40 minutes separately. How long will it take to fill the tanker from unfilled state if B is utilized for a fraction of the time and A and B fill it together for the other half?

Answer : D

Explanation

Let the total time taken be x minute. Then,
(1/40*x/2) + (1/60+ 1/40) x/2= 1 ⇒ x/80 + x/48 = 1
⇒3x+ 5x= 240 ⇒8x= 240 ⇒x= 30
Hence, the required time is 30 minutes.

Q 7 - If two funnels work at the same time, the repository will be filled in 12 hours. One channel fills the store 10 hours quicker than the request. How long does the speedier funnel take to fill the store?

Answer : C

Explanation

Suppose that one pipe takes x hours to fill the reservoir.
Than the other pipes takes (x-10) hours.
∴ 1/x+ 1/(x-10) = 1/12 ⇒12(x-10+x)= x(x-10)
⇒x²-34x +120=0 ⇒(x-30) (X-4) =0
⇒x= 30 or x= 4
So, the faster pipe takes 30 hrs to fill the reservoir.

Q 8 - A channel can fill a reservoir in 12 minutes and another funnel can fill it in 15 minutes, however a third pipe can discharge it in 6 minutes. The initial two funnels are kept open for 5 minute to start with and after that the third pipe is additionally opened. In what time is the storage exhausted?

Answer : D

Explanation

Part filled in 5 min= 5*(1/12+1/15)= (5*9/60)= 3/4
Part emptied in 1 min. when all the pipes are opened= 1/6 ? (1/12+1/15)
 = (1/6- 3/20) = 1/60
1/60 part is emptied in 1 min.
3/4 part will be emptied in (60*3/4) min = 45 min.

Q 9 - A pump can fill a tank with water in 2 hours. Because of a leak in the tank, it takes 7/3 hours to fill the tank. The leak can empty the filled tank in?

Answer : D

Explanation

Part of the tank filled by the pump in 1 hour = 1/2
Part of the tank filled by the pump in 1 hour because of the leak = 3/7
∴ Part of the tank emptied by the leak in 1 hour = 1/2 - 3/7
= 1/14
∴ Leak will empty the tank in 14 hours.

Q 10 - 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 1 hour each alternatively, the tank will be full in -

Answer : D

Explanation

Tank filled by (A+B) in 1 hour = (1/12 + 1/15) = 3/20
Tank filled by (A+C) in 1 hr = (1/12 + 1/20) = 2/15

∴ Part of tank filled in 2 hr = (3/20 + 2/15) = 17/60
∴ Part of tank filled in 6 hr = (3*17/60) = 17/20

Remaining part = 1 - 17/20 = 3/20

Now it is the turn of A and B and 3/20 is filled by A and B in 1 hour.

∴ Total time taken to fill the tank = (6+1) = 7 hr

aptitude_pipes_cisterns.htm

Print Page