The HCF of $475$ and $495$ is

Let $\frac{p}{q}$ be a rational number. Then, the condition on $q$ such that $\frac{p}{q}$ has a non terminating but repeating decimal expansion is

“Note: This question given in the book seems to have errors and the modified question should be as given below.”

Let $\frac{p}{q}$ be a rational number. Then, the condition on $q$ such that $\frac{p}{q}$ has a terminating decimal expansion is