Question

A cistern can be filled by 2 pipes a and b in 10 and 15 hrs respectively is then emptied by a tap in 8 hrs. If all the tap are opened the cistern will be filled in?

Answer 1

Answer:

24 hours

Step-by-step explanation:

a=1/10

b=1/15

empty=1/8

all together = 1/10 + 1/15 - 1/8 = (12+8-15)/120 = 5/120 = 1/24

total 24 hours