Aptitude Discussion

Q. |
Two taps can fill a tank in 12 min and 18 min respectively. Both the taps are kept open for 2 min and then the tap that fills the tank in 12 min is turned off. In how many more minutes will the tank be filled? |

✖ A. |
9 |

✖ B. |
12 |

✔ C. |
13 |

✖ D. |
10 |

**Solution:**

Option(**C**) is correct

In 2 minutes, the taps fill \(2\left(\dfrac{1}{12}+\dfrac{1}{16}\right)\) or \(\dfrac{5}{18}\)of the tank.

Therefore, \(\left(\dfrac{13}{18}\right)^{th}\)of the tank is to be filled by the second tap at the rate of \(\dfrac{1}{18}\) of the tank per minute.

This will take another **13 minutes.**

**Kyrie**

*()
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isn't it 1/18 instead of 1/16 in the first part