Question

two pipes can separately fill a tank in 3 hrs and 4 hrs respectively .if they are both used together how much time will they take to fill the tank. ​

Answer 1

Solution:

Let A be the first pipe, and B be the second. Then:

3A=1

4B=1

12A=4

12B=3

12(A+B)=7

A+B=7/12

1 tank=12/7 hours to fill, using both pipes…….