Adding and Subtracting Fractions with Unlike Denominators | Math with Mr. J
From Math with Mr. J
15 min5thMath
Summary
How to add and subtract fractions with unlike denominators by first finding a common denominator, then combining. Mr. J shows the full process with mixed numbers too.
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Teaching resources
Discussion questions
Fractions must have the same-size parts before you add or subtract -- so find a common denominator first.
- Why do you need a common denominator to add unlike fractions?
- How do you rewrite each fraction with the common denominator?
- What do you do after the denominators match?
Quick work-a-long
Words to know: common denominator, equivalent fraction, numerator
- Solve 1/2 + 1/3 by finding a common denominator.
- Solve 3/4 - 1/6 and simplify your answer if you can.