How do you add and subtract proper fractions?

Answer 1

If the denominators are the same, add or subtract the numerators. If the denominators are different, convert them to a common denominator and add or subtract the numerators.

2/3 - 1/3 = 1/3

4/5 - 2/3 = 12/15 - 10/15 = 2/15

Answer 2

The following also applies to comparing fractions. It works for both proper and improper fractions. Mixed fractions require additional considerations. You do the following:1) Find a common denominator

2) Convert all fractions to equivalent fractions, with the common denominator

3) Add, subtract, or compare the numerators

4) In the case of addition and subtraction, check whether you can simplify the resulting fraction

For example, if you want to add 1/6 + 1/2, the common denominator is 6, so you change that to 1/6 + 3/6. Adding the numerators (and keeping the denominator), you get 4/6. This can be simplified to 2/3.