Question

Question 2(iii)
Find the smallest number by which each of the following numbers must be multiplied to obtain a perfect cube:
72

Answer 1

72
Prime factors of $72=2\times 2\times 2\times 3\times 3$
Here 3 does not appear in 3’s group.
Therefore, 72 must be multiplied by 3 to make it a perfect cube.
$\begin{array}{cc}2& 72\\ 2& 36\\ 2& 18\\ 2& 9\\ 2& 3\\ & 1\end{array}$