Explain why it is necessary to have a common denominator when adding or subtracting fractions. Then solve 4/5 + 11/12

A common denominator allows you to add or subtract the numerators because the fractions are then representing parts of the same whole.

Adding and Subtracting Unlike Fractions

6th Grade•45 minutes

I can add and subtract fractions with unlike denominators.

When adding or subtracting fractions with unlike denominators, you must first find a common denominator.

To find a common denominator, find the least common multiple of the original denominators.

When you rename a fraction, remember that whatever you do to the denominator, you also have to do to the numerator to keep the fractions equivalent.

This lesson includes 5 practice questions to reinforce learning.

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1. What is the first step in adding or subtracting fractions with unlike denominators?

2. Find the sum of 2/5 and 3/10. Express your answer in simplest form.

3. Which of the following is equivalent to 1/4 + 2/3?

...and 2 more questions

Adding and Subtracting Fractions with Unlike Denominators | Math with Mr. J

Math with Mr. J