EXERCISE 3.4

Find the common factors of $20$ and $28$.

Find the common factors of $15$and $25$

Find the common factors of $35$and $50$.

Find the common factors of$5, 15$and $25$.

Find the first three common multiples of $6$ and $8$.

Find the first three common multiples of $12$and $18$ .

Are the following numbers co-prime?

$216$ and $215$

Are the following numbers co-prime?

$81$ and $16$