Question

1
12. A pipe can fill a tank with water in 3 hours. Due to leakage in bottom, it takes 3 1/2 hours to fill it. In what time will the leak enpty the tank​

Answer 1

A pipe takes 3 hours to fill

So in 1 hour it fills 1/3

Let the leakage take x hours to empty the tank

In 1 hour it empties 1/x of the tank

So together they fill 1/3- 1x of the tank in 1 hour

i.e. 1/3 - 1/x = 1/3.5

MULTIPLY BY 10.5x

3.5x - 10.5 = 3x

0.5x =10.5

x = 21 hours ANSWER