Question

A cubical tank has a volume of $15.625m^3$. Some water is drained from the tank and the depth of the water remaining in the tank is 1.3m. Find the volume of the water that was drained out.

Answer 1

Let each side of the cubical tank measures a m
Volume of water when the tank is full $=15.625m^3$
$\therefore$ Capacity of tank $=15.625m^3$
$\Rightarrow a^3=15.625m^3$
$\Rightarrow a=2.5m$
$\Rightarrow$ Depth of tank = 2.5 m
Depth of water =1.3 m
$\therefore$ Depth of empty tank = 2.5 m - 1.3 m = 1.2 m
Volume of water drained out = Volume of empty tank $=2.5\times 2.5\times 1.2m=75m^3$