Question

Question 6 (vi)

For the following number, find the smallest whole number by which it should be divided so as to get a perfect square. Also, find the square root of the square number so obtained:

1620

Answer 1

$1620=2\times 2\times 3\times 3\times 3\times 3\times 5$

Here, prime factor 5 has no pair. Therefore 1620

Must be divided by 5 to make it a perfect square.

$1620\times 5=324$

And $\sqrt{324}=2\times 3\times 3=18\begin{array}{cc}2& 1620\\ 2& 810\\ 3& 405\\ 3& 135\\ 3& 45\\ 3& 15\\ 5& 5\\ & 1\end{array}$