Question

What is the HCF of $12$ and $18$?

Answer 1

HCF of $12$ and $18$:

HCF is the largest of the common factors.

Factors of $12$ and $18$:

$$\begin{gathered} \mathrm{Factor}\mathrm{of}12=1,2,3,4,6,12 \\ \mathrm{Factor}\mathrm{of}18=1,2,3,6,9,18 \end{gathered}$$

Common factors of $12$ and $18$ is $1,2,3,6$

The highest common factors of $12$ and $18$ is $6$

$\therefore \mathrm{HCF}\left(12,18\right)=6$

Thus, HCF of $12$ and $18$ is $6$.