Simplifying fractions quiz for students. This is an online math test that focuses on teaching students how to simplify fraction values to their lowest terms. Always pay attention to fractions to find out if the numerator and denominator have any common factors. For example in the fraction 25/35, the common factor at this stage is 5. Both numbers when divided by five will reduce the fraction to 5/7. This procedure might occur in two steps in cases where the numbers can further be divided by a common factor. Test your skills on how to simplify fractions to the lowest terms and review 3rd, 4th, 5th and 6th grade math skills.