Question

1. Find the H.C.F. of the following numbers using prime factorization method:

(vii) $144,180,198$

Answer 1

First, do the prime factorization of the given numbers,

$$\begin{gathered} 144=2\times 2\times 2\times 2\times 3\times 3 \\ 180=2\times 2\times 3\times 3\times 5 \\ 198=2\times 3\times 3\times 11 \end{gathered}$$

We can see the common factors $=2\times 3\times 3$

So the H.C.F. of $144,180,198$ is $18$