Adding and Subtracting Fractions with Unlike Denominators

Mr. Leatherwood introduces the concept of adding and subtracting fractions with unlike denominators. He explains the importance of having the same denominator and demonstrates using models and numerical methods. The video covers finding the least common multiple to adjust denominators and provides examples of both addition and subtraction of fractions.

Why is it important to have the same denominators when adding or subtracting fractions?

• To simplify the process of addition or subtraction

• To make the fractions look similar

• To ensure the fractions are equivalent

• To avoid making the teacher sad

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2

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

• Add the numerators directly

• Find the least common multiple of the denominators

• Subtract the smaller denominator from the larger one

• Convert the fractions to decimals

Tags

CCSS.7.NS.A.1C

In the example of 4/10 + 3/5, what is the least common multiple of the denominators?

• 5

• 10

• 15

• 20

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2

After converting 3/5 to a fraction with a denominator of 10, what is the new fraction?

• 3/10

• 6/10

• 12/10

• 9/10

Tags

CCSS.3.NF.A.3B

CCSS.4.NF.A.1

What is the result of adding 4/10 and 6/10?

• 1/10

• 10/10

• 10/20

• 1

Tags

CCSS.4.NF.B.3C

CCSS.4.NF.B.3D

In the example of 3/7 + 2/21, what is the least common multiple of the denominators?

• 28

• 14

• 21

• 7

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2

What is the new fraction when 3/7 is converted to have a denominator of 21?

• 12/21

• 3/21

• 6/21

• 9/21

Tags

CCSS.3.NF.A.3B

CCSS.4.NF.A.1

What is the result of adding 9/21 and 2/21?

• 10/21

• 12/21

• 11/21

• 9/21

Tags

CCSS.4.NF.B.3C

CCSS.4.NF.B.3D

In the example of 3/4 - 5/12, what is the least common multiple of the denominators?

• 12

• 8

• 16

• 4

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2

What is the simplified result of subtracting 5/12 from 9/12?

• 2/3

• 1/2

• 1/3

• 1/4

Tags

CCSS.4.NF.B.3C

CCSS.4.NF.B.3D