Aptitude - Pipes and Cistern - Discussion
Discussion Forum : Pipes and Cistern - General Questions (Q.No. 6)
6.
Two pipes can fill a tank in 20 and 24 minutes respectively and a waste pipe can empty 3 gallons per minute. All the three pipes working together can fill the tank in 15 minutes. The capacity of the tank is:
Answer: Option
Explanation:
| Work done by the waste pipe in 1 minute = | 1 | - |  |
1 | + | 1 |  |
| 15 | 20 | 24 |
| = | |
1 | - | 11 | |
| 15 | 120 |
| = - | 1 | . [-ve sign means emptying] |
| 40 |
 Volume of |
1 | part = 3 gallons. |
| 40 |
Volume of whole = (3 x 40) gallons = 120 gallons.
Discussion:
48 comments Page 4 of 5.
Prasna said:
8 years ago
Take the LCM of 24 and 20, you will get the Answer is 120.
Jeevitha said:
5 years ago
Thanks a lot @Gohor. Your method is simple to understand.
(2)
Arshiya said:
1 decade ago
11/120 is the time taken by two pipes to fill the tank.
Aqueeb Khan said:
9 years ago
How can we solve this problem by the unitary method?
Ragi said:
10 years ago
15(x/20+x/24-3) = x.
(11x-120)/8 = x.
x = 40 gallon.
(11x-120)/8 = x.
x = 40 gallon.
Sujit baji said:
10 years ago
(1/15 - 11/120) = -1/40 how? please explain it.
Raj said:
1 decade ago
How did 1/20+1/24=11/120.
Please explain it ?
Please explain it ?
Puja banerjee said:
8 years ago
Thanks for the explanation @Bhakta B Monger.
Preethi said:
5 years ago
@Krish.
Your explanation is good. Thanks.
Your explanation is good. Thanks.
Mouni said:
1 decade ago
How did -1/40? Please explain it.
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