Question

The volume of a closed cubical tank is 1331 cu m. Find the length of the side of the cubical tank.

• A. 12 m
• B. 13 m
• C. 11 m
• D. 20 m

Answer 1

The correct option is C

11 m

Let the side of the given cubical tank be 'a' metres .

Volume of the given cube is $a\times a\times a$

Length of the side of cubical tank = $\sqrt[3]{3volume}$

Given: Volume = 1331 cu m

Length of the side of cubical tank = $\sqrt[3]{31331}$

Prime factorization of 1331:
$\begin{array}{cc}11& 1331\\ 11& 121\\ 11& 11\\ & 1\end{array}$
$1331=11\times 11\times 11={11}^3$
$\therefore$ Cube root of 1331 is 11.

Hence, the length of the side of the cube = 11 m