Question

How to make 256 a perfect cube?

• A. Divide by 4
• B. Divided by 8
• C. Divide by 2
• D. Multiply by 2

Answer 1

Answer: (A), (D)

Multiply by 2

$\begin{array}{cc}2& 256\\ 2& 128\\ 2& 64\\ 2& 32\\ 2& 16\\ 2& 8\\ 2& 4\\ 2& 2\\ & 1\end{array}$

Prime factor of 256 = 2 $\times$ 2 $\times$ 2$\times$ 2 $\times$ 2 $\times$ 2 $\times$ 2 $\times$ 2 = $2^8$
So, to make 256 a perfect cube, we either need to multiply with 2 to make it $(2^3{)}^3$ or divide it by 4 to make it 64 which is $4^3$.