A pipe can fill a water tank three times as fast as another pipe. If both are used together, they can fill the tank in 36 minutes. How much time will be taken by the slower pipe alone to fill the tank?
A192 minutes
B108 minutes
C144 minutes ✓ Correct
D160 minutes
Correct answer: (C) 144 minutes
Explanation
The slower pipe alone takes 144 minutes.
Let the slower pipe fill in t minutes, the faster in t/3.
Combined rate: 1/t + 3/t = 1/36.
4/t = 1/36.
t = 4 * 36 = 144 minutes.
Want more like this? Create a free account to practise a full test, track your progress, and get spaced-repetition review.
Practise on Mcqkart →🎓 Book an expert →