Explain what it means to express a fraction in simplest form

In simplest form means to find the greatest common factor that can go into both the numerator and denominator.

Example:
20/10 simplified to 2/1 or 2

This fraction can be simplified by 10 because 10 goes into both the numerator and denominator. 5 also goes into both, but the greatest common factor is 10.

The simplest form of a fraction is when the top and bottom cannot be any smaller.