Adding & Subtracting Fractions with UNLIKE Denominators

Front

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

Back

Find a common denominator for the fractions.

Tags

CCSS.7.NS.A.1C

Front

How do you find the least common denominator (LCD) for two fractions?

Back

List the multiples of each denominator and find the smallest multiple they have in common.

Front

What is the formula for adding fractions with unlike denominators?

Back

(a/b) + (c/d) = (a*d + b*c) / (b*d) where b and d are the denominators.

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2

Front

What is the formula for subtracting fractions with unlike denominators?

Back

(a/b) - (c/d) = (a*d - b*c) / (b*d) where b and d are the denominators.

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2

Front

When adding fractions, what do you do with the numerators?

Back

You add the numerators together after finding a common denominator.

Tags

CCSS.4.NF.B.3C

CCSS.4.NF.B.3D

Front

When subtracting fractions, what do you do with the numerators?

Back

You subtract the second numerator from the first after finding a common denominator.

Tags

CCSS.4.NF.B.3C

CCSS.4.NF.B.3D

Front

What is an example of a common denominator for the fractions 1/2 and 1/3?

Back

The common denominator is 6.

Front

If you have the fractions 5/9 and 1/6, what is their common denominator?

Back

The common denominator is 18.

Front

What is the result of adding 5/9 and 1/6?

Back

The result is 13/18.

Tags

CCSS.7.NS.A.1C

Front

How do you convert fractions to have a common denominator?

Back

Multiply the numerator and denominator of each fraction by the necessary factor to reach the common denominator.