Question

Pipe A can fill a tank in 20 hours and pipe B can fill the same tank in
18 hours. If both the pipes are opened together, then time to fill the same tank is
a.
$8 \frac{9}{19} \: hours$
b.
$10 \frac{9}{19} \: hours$
c.
$9 \frac{9}{19} \: hours$
d.
$11 \frac{9}{19} \: hours$
​

Answer 1

Answer:

option A is correct answer