TITLE: How do you find the number of multiples of a given range of numbers?
QUESTION [13 upvotes]: I know this sounds a bit stupid but this question always confounds me. Say that you are given a range of numbers like $20$-$300$. And it asks you to find how many multiples of $5$ are given in that range. How would you proceed? What would the answers be for inclusive and exclusive numbers?

REPLY [3 votes]: This may be logically equivalent to Bhaskar Vashishth’s answer, but IMNSHO this is clearer.

Figure out how many multiples of $5$ there are between $0$ and $300$. 
Hint: $\frac{300}5$ may have something to do with this.
Figure out how many multiples of $5$ there are between $0$ and $20$.
Subtract result 2 from result 1.