Divide a Fraction by a Fraction

Divide a Fraction by a Fraction

by Ms. Tout

Warm Up​

​

Multiple Choice

  $$\frac{8}{9}\div10$$  

• 8/90

• 80/9 = 8 2/3

• 18/9 = 2

• 8/19

Multiple Choice

  $$21\div\frac{3}{4}$$  

• 24/4 = 6

• 84/63

• 28

• 24/25

​Invisible Math

​Remember:

​

​ALL whole numbers have a denominator of 1.

Multiple Choice

How do you multiply fractions?

• Cross Diagonals

• Straight Across

• Cross subtraction

• Numerator x Denominator

​Vocabulary

• ​Reciprocal - the flipped or inverse of a fraction

Multiple Choice

What is the reciprocal of 2

• 4

• 1/2

• 2/1

• 2/2

Multiple Choice

What is the reciprocal of  $$\frac{5}{8}$$  

• $$\frac{8}{5}$$  

• $$\frac{5}{8}$$

• $$-\ \frac{5}{8}$$  

• $$-\ \frac{8}{5}$$  

Multiple Choice

What is the reciprocal of 5?

• 5/1

• 1/5

​Steps to Solve

• ​Step 1: Keep the first fraction

• ​Step 2: Change

• ​Step 3: Flip the second fraction

  • ​Reciprocal!

• ​Step 4: Multiply Across

• ​Step 5: Simplify if needed

Multiple Choice

What fraction do we Keep the same or Leave alone?

• the division sign

• first fraction

• the third decimal

• the second fraction

Multiple Select

What do we mean by Flip?

• Flip the numbers upside down

• rotate the location of numerator and denominator

• write the reciprocal

• the fraction does a backflip

​Example:

• ​Step 1: K.C.F.

  • ​Reciprocal of 1/3 = 3/1

• ​Step 2: Multiply

• ​Step 3: Simplify

​Example:

​Step 1: Keep 2/3

​

​Step 2: Change

​

​Step 3: Flip 1/4 --> 4/1

​

​Step 4: Multiply Across

​ 2 x 4 = 8

​3 x 1 = 3

​

​Step 5: Simplify

Multiple Choice

2/5  ÷ 3/4

• 8/15

• 6/20

• 3/10

• 3/20

Multiple Choice

¹/₄  ÷  ²/₅

• ⁵/₈

• 2/20

• ¹/₁₀

• ³/₉

Multiple Choice

⁴/₉  ÷  ¹/₂

• ⁸/₉

• ⁵/₁₁

• ⁶/₁₀

• ⁴/₁₈

Multiple Choice

Divide. 1/3 ÷ 1/2

• 2/3

• 1/6

• 4/8

• 1 1/2

Multiple Choice

1/2 divided by 3/4

• 3/2

• 2/3

• 1 1/2

• 3/8

Multiple Choice

³⁄₄ ÷ ¹⁄₂ =

• 1  1/2

• ⁶⁄₈

• ³⁄₈

• ¹⁄₂

Multiple Choice

What method do we use to divide fractions

• Freeze

  Shake

  Flip

• Flip

  Jump

  Multiply

• Keep 

  Change 

  Flip

• Divide

  Divide

  Divide