What this worksheet covers
To simplify a fraction a student divides the top and bottom by the same common factor until no common factor is left. Each problem here is built by multiplying a fraction already in lowest terms by a factor from 2 to 5, so there is always something to reduce and the answer is always a proper fraction with no common factor. Denominators in the problems go up to 12.
Who it is for
Fifth and sixth grade, as a support for adding and subtracting fractions. Fourth graders meet the idea under 4.NF.A.1, as equivalence in the other direction. It also leads into the greatest common factor, which is on its own sheet in the maker.
Writing a fraction in lowest terms · grades 5 and 6
A worked example
6/8: both numbers divide by 2, giving 3/4, and 3 and 4 share no factor, so it is finished. For 8/12, divide by 4 at once and get 2/3, or divide by 2 twice, which reaches the same place. Ask students why both routes work.
Mistakes to watch for
- Stopping too soon, so 8/12 becomes 4/6. Ask whether any number divides both 4 and 6.
- Subtracting the same number from top and bottom instead of dividing, so 6/8 becomes 4/6. Fraction strips show the amount has changed.
Make it your own
This sheet is one setting of the math worksheet generator. Open it there to change the skill, the range of numbers or the heading, or to mix several skills on one sheet.