Question

Find the $HCF$ of $28$ and $126$ by prime factor method.

Answer 1

Prime factorization of $28$

$28=2\times 2\times 7=2^2\times 7^1$

Prime factorization of $126$

$126=2\times 3\times 3\times 7=2^1\times 3^2\times 7^1$

Therefore,

$HCF(28,126)=2^1\times 3^0\times 7^1=14$