Question

Find the cube root of 681492.

• A. 66
• B. 77
• C. 99
• D. 88

Answer 1

The correct option is D

88

$\begin{array}{cc}11& 681472\\ 11& 61952\\ 11& 5632\\ 2& 512\\ 2& 256\\ 2& 128\\ 2& 64\\ 2& 32\\ 2& 16\\ 2& 8\\ 2& 4\\ 2& 2\\ & 1\end{array}$

Prime factor of 681492 = 2 $\times$ 2 $\times$ 2 $\times$ 2 $\times$ 2 $\times$ 2 $\times$ 2 $\times$ 2 $\times$ 2 $\times$ 11 $\times$ 11 $\times$ 11

Cube root of 681472 = $\sqrt[3]{32^3\times 2^3\times 2^3\times {11}^3}$ = 88