adding & subtracting fractions with same denominators steps; 1) add or subtract the numerators...

Adding & Subtracting Fractions with Same Denominators

Steps;

1) Add or subtract the numerators

2) Keep the denominator the same

3) Simplify by reducing to lowest terms

Adding & Subtracting Fractions with Different Denominators

Steps;

1) Find a common denominator• List multiples• Multiply the denominators

2) Make equivalent fractions

3) Add or subtract the numerators

4) Keep the denominator the same

5) Simplify by reducing to lowest terms

We need a common denominator to add

these fractions.

7, 14, 21, 28, 35…

2, 4, 6, 8, 10, 12, 14, 16, 18, 20

We need a common denominator to add

these fractions.

7, 14, 21, 28, 35…

2, 4, 6, 8, 10, 12, 14, 16, 18, 20

The first number IN COMMONthat appears on both lists

becomes the common denominator

x 2

x 2

X 7

x 7 7

6

7 + 6 = 13

13

We need a common denominator to add

these fractions.

5, 10, 15, 20, 25, 30, 35, 40, 45

7, 14, 21, 28, 35, 42, 49, 56, 63

x 7

x 7

X 5

x 5 15

7

15 + 7 = 22

22

We need a common denominator to add

these fractions.

7, 14, 21, 28, 35, 42, 49, 56, 63

8, 16, 24, 32, 40, 48, 56, 64, 72

x 7

x 7

x 8

x 8 32

2132 + 21 = 53

53

We need a common denominator to add

these fractions.

3, 6, 9, 12, 15, 18, 21, 24, 27

5, 10, 15, 20, 25, 30, 35, 40, 45

X 3

x 5

x 5

x 3 9

10

9 + 10 = 19

19

We need a common denominator to add

these fractions.

3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33

11, 22, 33, 44, 55, 66, 77…

x 11

x 11

X 3

x 3 15

2215 + 22 = 37

37

We need a common denominator to add

these fractions.

3, 6, 9, 12, 15, 18, 21, 24, 27

6, 12, 18, 24,…

x 1

x 1

X 2

x 2 4

1

4 + 1 = 5 5

We need a common denominator to add

these fractions.

11, 22, 33, 44, 55, 66, 77…

6, 12, 18, 24, 30, 36, 42, 48, 54, 60, 66, 72

x 11

x 11

X 6

x 6 18

11

29

18 + 11 = 29

We need a common denominator to add

these fractions.

We need a common denominator to add

these fractions.

9, 18, 27, 36, 45, 54, 63, 72, 81

5, 10, 15, 20, 25, 30, 35, 40, 45

9, 18, 27, 36, 45, 54, 63, 72, 81

5, 10, 15, 20, 25, 30, 35, 40, 45

The first number IN COMMONthat appears on both lists

becomes the common denominator

x 5

x 5

x9

x 936

3536 + 35 = 71

71

36 + 35 = 71

We need a common denominator to add

these fractions.

12, 24, 36, 48, 60, 72, 84, 96

8, 16, 24, 32, 40, 48, 56, 64, 72, 79, 80, 88, 96

x 3

x 3

x 2

x 2

19

10 + 9 = 19

9

10

5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55

We need a common denominator to

subtract a fraction from another.

11, 22, 33, 44, 55, 66, 77…

x 5

x 5

x 11

x 11

4

15 - 11 = 4

15

11

We need a common denominator to

subtract one fractionfrom another.

2, 4, 6, 8, 10, 12, 14, 16, 18, 20 …

10, 20, 30…

x 1

x 1

x 5

x 5

2

5 – 3 = 2

5

3

Try These

A

F

EB

C

D

Try These Answers

A

F

EB

C

D1727

1920

109

4128

2621

1312

Board Game Challenge

• http://www.math-play.com/adding-and-subtracting-fractions-game.html