Question

A tap can empty a tank in 45 minutes. A second tap can empty it in 30 minutes. If both the taps operate
simultaneously, how much time is needed to empty the tank?
(a) 18 min.
(b) 20 min.
(c) 40 min
(d) 45 min​

Answer 1

Answer:

18 min

Step-by-step explanation:

A tap can empty the tank in 45 minutes

In 1 minutes it can empty 1/45 part of the tank

Second tap , in 1 minutes it can empty 1/30 part of the tank

in 1 minutes both tap can empty

= 1/45 + 1/30 part

= (2+3)/90 part

=5/90 part

= 1/18 part.

Therefore, both tap take time to empty the full part of the tank = 18 minutes