Question

A tap can empty a tank in 20 hours while another tap can empty it in 15 hours. If both taps are open simultaneously, how long will it take to empty the full tank?

Answer 1

Step-by-step explanation:

1/20+1/15=7/60

7/60 part fill in 1 hour

1 part fill in 1÷7/60= 60/7 hour