Question

A water pump takes $6hours$ to fill an overhead tank. The standby pump takes $10hours$ to fill the same tank. If the first pump fails after $2hours$ then how long will the standby pump take to fill the rest?

Answer 1

Step 1: Find the amount of water to fill in two hours.

A water pump takes $6hours$to fill an overhead tank.

The standby pump takes $10hours$ to fill the same tank.

$1hour=\frac{1}{6}$ of the tank

$2hours=\frac{1}{6}x2=\frac{1}{3}$ of the tank

Find the amount of water to be filled:

Amount of water to be filled $=1–\frac{1}{3}=\frac{2}{3}$ of the tank

Step 2: Finding the number of hours needed for the standby pump to fill the tank:

The standby pump takes $10hours$to fill the tank

$1\tan k=10hour$

$\frac{2}{3}$ of the tank $=\frac{2}{3}x10=\frac{20}{3}hours=6hours40mins$

Hence, It will take$6hours40mins$ for the standby pump to fill up the rest of the tank.