Question

Two taps, A and B, can fill a tank (of capacity 210 litre) in 24 hours and 14 hours respectively. If both the
taps are opened simultaneously and alter 4 hours both the taps are closed, what quantity of water Is lo be
added lo the tank to fill It completely? (in litre)

Answer 1

Rate of tap A = 210/24 = 35/4 litre per hour
Rate of tap B = 210/14 = 15 litres per hour

When opened simultaneously, they fill  35/4 + 15                                   = 95/4 litres per hour

In 4 hours, they fill = 95/4  x 4                                                            = 95 litres
The amount that need to be added = 210 – 95                                                                            = 115 litres