Find out how to add and subtract fractions with matching and different denominators in this video, activity and Second Level Maths Bitesize Guide.

The common denominator model, while not really a picture, demonstrates that the same rules apply to multiplication and division with fractions. It also shows why “invert and multiply” works.

In addition to emphasizing fractions as points on the number line, the common standards differ from previous standards in other important ways: They delay arithmetic with fractions until students ...

In adding and subtracting fractions with unlike denominators, you have to get a least common denominator which is exactly like the least common multiple it just so happens to be in the denominator.