Course 1Course 1

Fractions With Unlike DenominatorsFractions With Unlike DenominatorsLESSON 5-3LESSON 5-3

Find + .12

13

Method 1 Model + .12

13

+ = 12

13

56

Use the fraction model for .

Use the fraction model for .12

13

Additional Examples

Course 1Course 1

Fractions With Unlike DenominatorsFractions With Unlike DenominatorsLESSON 5-3LESSON 5-3

(continued)

Method 2 Use a common denominator.

Add the numerators.56

1 3

2 3

12

36

+

13 The LCD is 6. Write the fractions

with the same denominator.

1 2

3 2

+

26

Additional Examples

Course 1Course 1

Fractions With Unlike DenominatorsFractions With Unlike DenominatorsLESSON 5-3LESSON 5-3

Add the numerators.1415

Add and to find the fraction of students who chose cheese or pepperoni.35

13

The favorite pizza topping of of the students is either cheese or pepperoni.1415

13

1 5

3 5 +

35 The LCD is 15. Write the fractions

with the same denominator.

3 3

5 3

+ 515

915

Additional Examples

In Ms. DeMarco’s class, of the students chose

cheese as their favorite pizza topping. Pepperoni was

chosen by of the students. What fraction of the students

chose either cheese or pepperoni as their favorite pizza

topping?

35

13

Course 1Course 1

Fractions With Unlike DenominatorsFractions With Unlike DenominatorsLESSON 5-3LESSON 5-3

Find – .16

58

Method 1 Model – .16

58

– = 16

58

1124

Use the fraction model for .

Use the fraction model for .16

58

Additional Examples

Course 1Course 1

Fractions With Unlike DenominatorsFractions With Unlike DenominatorsLESSON 5-3LESSON 5-3

(continued)

Method 2 Use a common denominator.

Subtract the numerators.1124

16

1 4

6 4 –

58 The LCD is 24. Write the fractions

with the same denominator.

5 3

8 3

– 424

1524

Additional Examples