To convert a mixed number to an improper fraction you must multiply the denominator by the whole number, then add the numerator.
So with 8 2/5 it would look like this:
5 * 8 + 2
40 + 2
= 42
Remember you keep the same denominator though. So, the improper fraction would be:
42/5
Hope this helps you! Happy Thanksgiving, here's a turkey!