The question:
Determine the number of positive integers that divide at least one of the numbers $3680$ and $100$.
The answer:
We have that $3680 = 2^5\cdot5\cdot23$ and $100 = 2^2\cdot5^2$
The number of positive integers dividing $3680$ is therefore $6\cdot2\cdot2$, the number of positive integers dividing $100$ is $3\cdot3$, and the number of positive numbers that divide both $3680$ and $100$ is $3\cdot2$. The number sought is thus $24 + 9 − 6 = 27$
What I need help with
I don't understand the resesing for dividing $3680$ is therefore $6\cdot2\cdot2$ and dividing $100$ is $3\cdot3$