A tyre has two punctures. The first puncture alone would have made the tyre flat in 9 minutes and the second alone would have done it in 4 minutes. If air leaks out at a constant rate, how long does it take both the punctures together to make it flat ?
Choose the correct choice from the following.
A) 3 1/5min	B) 2 10/13min	C) 3 3/5min	D) 3 4/5min	E) 3 min
Explanation:   Do not be confused, Take this question same as that of work done question's. Like work done by 1st puncture in 1 minute and by second in 1 minute.   Lets Solve it:   1 minute work done by both the punctures =   (1/9+1/4)=(13/36)   So both punctures will make the type flat in   (36/13)mins=2 10/13mins   Option 2 10/13min
<result>B</result>
A tyre has two punctures. The first puncture alone would have made the tyre flat in 9 minutes and the second alone would have done it in 4 minutes. If air leaks out at a constant rate, how long does it take both the punctures together to make it flat ?