Adding and Subtracting Fractions

To add or subtract fractions, you need...

• a common denominator.

• a common numerator.

Tags

CCSS.4.NF.B.3C

CCSS.4.NF.B.3D

With a common denominator, you can...

• add or subtract fractions.

• multiply or divide fractions.

Tags

CCSS.4.NF.B.3C

CCSS.4.NF.B.3D

A common denominator can be found by...

• finding the LCM of the denominators.

• finding the GCF of the denominators.

If you find the LCM of the denominators, you find the...

• common denominator.

• common numerator.

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2

What's the common denominator of 1/2 and 3/4?

• 4

• 2

• 6

• 8

What's the least common denominator of 5/6 and 11/12?

• 12

• 6

• 72

• 24

Do you need a common denominator when you multiply or divide fractions?

• No, only when you add or subtract.

• Yes, you do.

Tags

CCSS.5.NF.B.6

What's the common denominator of 2/3 and 1/6?

• 6

• 3

• 18

• 9

What's the LCM of 5 and 10?

• 5

• 10

• "Quizizz ruined my life." -Baron

What's the common denominator of 4/5 and 1/10

• 10

• 5

• 50

• 20