Question

Find the smallest whole number by which $252$ should be divided, so as to get a perfect square.

Answer 1

By prime factorisation of $252$, we get

$252=2\times 2\times 3\times 3\times 7$

Here $2$ and $3$ are in pair, but $7$ has no pair which can be eliminated after dividing $768$ by $7$.

Hence, $252$ needs to be divided by $7$ to become a perfect square.