Aptitude - Pipes and Cistern - Discussion
Discussion Forum : Pipes and Cistern - General Questions (Q.No. 9)
9.
Two pipes A and B can fill a tank in 20 and 30 minutes respectively. If both the pipes are used together, then how long will it take to fill the tank?
Answer: Option
Explanation:
| Part filled by A in 1 min = | 1 | . |
| 20 |
| Part filled by B in 1 min = | 1 | . |
| 30 |
| Part filled by (A + B) in 1 min = |  |
1 | + | 1 |  |
= | 1 | . |
| 20 | 30 | 12 |
Both pipes can fill the tank in 12 minutes.
Discussion:
15 comments Page 2 of 2.
Jigme wangdi said:
1 decade ago
How comes 3+2?
Karthik said:
1 decade ago
How did you get (1/20+1/30)+1/12?
Sanjana said:
1 decade ago
LCM of 20 and 30 is 60.
Solve,
1/20+1/30.
= 3+2/60.
= 5/60.
= 1/12.
Solve,
1/20+1/30.
= 3+2/60.
= 5/60.
= 1/12.
Ramkumar said:
1 decade ago
1/20 + 1/30 = 2/50 so = 1/25.
Then how it is possible of 1/12.
Then how it is possible of 1/12.
Mahadev said:
1 decade ago
How 1/12 is coming please explain?
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