Practice Subtracting Fractions with Unlike Denominators in Math

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Quick Recap

Subtracting fractions with different denominators by first rewriting them with a common denominator, then subtracting numerators.

To find \frac{3}{4} - \frac{1}{3}, convert to twelfths: \frac{9}{12} - \frac{4}{12} = \frac{5}{12}. Same idea as addition, just subtract.

Example 1

easy
Subtract \frac{3}{4} - \frac{1}{6}.

Example 2

medium
A runner completed \frac{7}{8} of a race, then stopped. If the race is 1 km long, what fraction of the race is left? If another runner has already finished \frac{2}{5} of the remaining distance, how much of the total race has that runner covered?

Example 3

easy
Compute \frac{5}{6} - \frac{1}{4}.

Example 4

hard
Compute \frac{11}{12} - \frac{3}{8} - \frac{1}{6}.