Question:
Tick (✓) the correct answer:
6 pipes fill a tank in 120 minutes, then 5 pipes will fill it in
(a) 100 min
(b) 144 min
(c) 140 min
(d) 108 min
Solution:
(b) 144 min
Let x min be the time taken by 5 pipes to fill the tank.
| No. of pipes | 6 | 5 |
| Time (in min) | 120 |
Now, $6 \times 120=5 \times x$
$\Rightarrow x=144$
Therefore, 5 pipes will take 144 min to fill the tank.