Question

The smallest natural number by which $392$ must be multiplied so as to get a Perfect Cube is :

• A. 2
• B. 7
• C. 4
• D. 5

Answer 1

The correct option is B 7

$392$ can be factorised into

$392=\left(2^3\right)\ast \left(7^2\right)$

for it to be a perfect cube its prime factors power must be a multiple of $3$

therefore it must be multiplied by $7$