Multiplying Fractions

Multiplying Fractions 8 9 3 4 24 36 2 3 12 x = = ÷ 12

Multiplying Fractions 1 2 5 9 5 18 x =

Multiplying Fractions 2 3 15 28 30 84 5 14 6 x = = ÷ 6

Multiplying Fractions – Simplifying with cross - canceling 8 9 3 4 8 4 9 3 3 3 4 4 ÷ ÷ x = x ÷ ÷ ÷ GCF = 3 GCF = 4 2 3 2 3 1 = x =

Multiplying Fractions – Simplifying with cross - canceling 1 2 5 9 1 1 2 1 5 1 9 1 ÷ ÷ x = x ÷ ÷ ÷ GCF = 1 GCF = 1 5 18 1 2 5 9 = x =

Multiplying Fractions – Simplifying with cross - canceling 2 3 15 28 2 2 3 3 15 3 28 2 ÷ ÷ x = x ÷ ÷ ÷ GCF = 3 GCF = 2 5 14 1 5 14 = x =

BONUS ROUND

To divide fractions 1. Take reciprocal of number you are dividing by (divisor) Multiply dividend and reciprocal of divisor (straight across) 3. Simplify answer (if necessary)

REVIEW

& dding ubtracting ractions

We need a common denominator to add these fractions. +

+ We need a common denominator to add these fractions. Count by 2's 2, 4, 6, 8, 10, 12, 14, 16, 18, 20 Count by 7's 7, 14, 21, 28, 35…

Count by 2's 2, 4, 6, 8, 10, 12, 14, 16, 18, 20 Count by 7's 7, 14, 21, 28, 35… The first number IN COMMON that appears on both lists becomes the common denominator

7 6 13 = = + 7 + 6 = 13 x 7 X 7 x 2 x 2 Make equivalent fractions. Add the numerators = + 7 + 6 = 13 x 2 13

+ We need a common denominator to add these fractions. Count by 7's 7, 14, 21, 28, 35, 42, 49, 56, 63 Count by 5's 5, 10, 15, 20, 25, 30, 35, 40, 45

15 7 22 = + = 15 + 7 = 22 x 5 X 5 x 7 x 7 Make equivalent fractions. Add the numerators = x 7 15 + 7 = 22 22

We need a common denominator to add these fractions. + Count by 7's 7, 14, 21, 28, 35, 42, 49, 56, 63 Count by 8's 8, 16, 24, 32, 40, 48, 56, 64, 72

32 21 53 32 + 21 = 53 = + = x 8 x 8 x 7 x 7 Make equivalent fractions. Add the numerators x 7 + 32 + 21 = 53 = x 7 53

+ We need a common denominator to add these fractions. Count by 3's 3, 6, 9, 12, 15, 18, 21, 24, 27 Count by 5's 5, 10, 15, 20, 25, 30, 35, 40, 45

x 3 9 Add the numerators = X 3 9 + 10 = 19 x 5 10 + = x 5 19

+ We need a common denominator to add these fractions. Count by 3's 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33 Count by 11's 11, 22, 33, 44, 55, 66, 77…

15 22 37 = + = 15 + 22 = 37 x 3 X 3 x 11 x 11 Make equivalent fractions. = X 3 x 11 Add the numerators 22 + = 15 + 22 = 37 x 11 37

+ We need a common denominator to add these fractions. Count by 3's 3, 6, 9, 12, 15, 18, 21, 24, 27 Count by 6's 6, 12, 18, 24,…

4 1 5 4 + 1 = 5 = + = x 2 X 2 x 1 x 1 Make equivalent fractions. Add the numerators = x 1 4 + 1 = 5 5

+ We need a common denominator to add these fractions. Count by 11's 11, 22, 33, 44, 55, 66, 77… 6, 12, 18, 24, 30, 36, 42, 48, 54, 60, 66, 72

18 11 29 = + = 18 + 11 = 29 x 6 X 6 x 11 x 11 Make equivalent fractions. = X 6 x 11 11 + Add the numerators. = 18 + 11 = 29 x 11 29

We need a common denominator to add these fractions. +

+ We need a common denominator to add these fractions. Count by 5's 5, 10, 15, 20, 25, 30, 35, 40, 45 Count by 9's 9, 18, 27, 36, 45, 54, 63, 72, 81

Count by 5's 5, 10, 15, 20, 25, 30, 35, 40, 45 Count by 9's 9, 18, 27, 36, 45, 54, 63, 72, 81 The first number IN COMMON that appears on both lists becomes the common denominator

x 9 36 Make equivalent fractions. Make equivalent fractions. = x9 x 5 35 Add the numerators. Add the numerators. + = 36 + 35 = 71 36 + 35 = 71 x 5 71

+ We need a common denominator to add these fractions. Count by 12's 12, 24, 36, 48, 60, 72, 84, 96 Count by 8's 8, 16, 24, 32, 40, 48, 56, 64, 72, 79, 80, 88, 96

10 9 19 10 + 9 = 19 = + = x 2 x 2 x 3 x 3 Make equivalent fractions. Add the numerators. + = 10 + 9 = 19 x 3 19

- We need a common denominator to subtract a fraction from another. Count by 5's 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55 Count by 11's 11, 22, 33, 44, 55, 66, 77…

15 11 4 15 - 11 = 4 = = - x 5 x 5 x 11 x 11 Make equivalent fractions. Subtract. = 15 - 11 = 4 - x 11 4

- We need a common denominator to subtract one fraction from another. Count by 2's 2, 4, 6, 8, 10, 12, 14, 16, 18, 20 … Count by 10's 10, 20, 30…

5 3 2 5 – 3 = 2 = - = x 5 x 5 x 1 x 1 Make equivalent fractions. Subtract. - = 5 – 3 = 2 x 1 2

Try These A D E B F C

Try These(Answers) 10 9 17 27 A D 41 28 13 12 B E 19 20 26 21 C F