Let $M$ be the number of multiples of 5 between 1 to 2020 inclusive and $N$ be the number of multiples of 20 between 1 and 2020 inclusive. What is the value of $10 M \div N$.

##
Since $2020=5 \times 404$, the positive multiples of 5 less than or equal to 2020 are

$$
5 \times 1,5 \times 2,5 \times 3, \ldots, 5 \times 403,5 \times 404
$$

so there are 404 positive multiples of 5 less than or equal to 2020 . This means $M=404$.

Similarly, the number of multiples of 2020 between 1 and 2020 is $N=\frac{2020}{20}=101$.

Thus, $10 M \div N=4040 \div 101=40$.