Question

Find the prime factorisation of $221$.

Answer 1

Solve by prime factorisation:

Given number is $221$

$$\begin{gathered} \begin{array}{cc}13& 221\\ 17& 17\\ & 1\end{array} \\ \Rightarrow 221=13\times 17 \end{gathered}$$

Therefore, the prime factorisation of $221$ is $13\times 17$.