Dividing Fractions

Dividing Fractions

To find the reciprocal

flip the fraction over

Multiple Choice

What is the reciprocal of $\frac{7}{8}$  ?

• 1

•  $\frac{14}{16}$  

•  $\frac{8}{7}$ 

•  $\frac{7}{8}$ 

Multiple Choice

Find the reciprocal of  $\frac{7}{11}$  

• 1 $\frac{1}{7}$  

•  $\frac{11}{11}$  

•  $\frac{11}{7}$  

•  $\frac{7}{7}$  

Reciprocal of a Whole Number

Remember

-all whole numbers can be made into fractions by putting a 1 as the denominator.

Multiple Choice

Find the reciprocal of 11

• $\frac{11}{1}$

• $\frac{11}{11}$

• 1 $\frac{1}{11}$

• $\frac{1}{11}$

Multiple Choice

Find the reciprocal of 7

• 
  $\frac{1}{7}$

• $\frac{7}{1}$

• 1 $\frac{1}{7}$

• $\frac{7}{7}$

To find the reciprocal of a Mixed Number

you first have to make it an improper fraction, then flip.

Multiple Choice

What is the reciprocal of 3  $\frac{2}{5}$  

• 3  $\frac{5}{2}$  

•  $\frac{5}{6}$  

•  $\frac{17}{5}$  

•  $\frac{5}{17}$  

Multiple Choice

What is the reciprocal of  $2\ \frac{1}{4}$  ?

•  $\frac{9}{4}$ 

•  $\frac{4}{9}$  

•  $2\ \frac{4}{1}$  

•  $4\ \frac{1}{2}$ 

Let's practice rewriting division problems as multiplication problems.

Multiple Choice

Rewrite as a multiplication expression:

 $\frac{2}{3}\div\frac{1}{2}$  

Remember - Keep, Change, Flip

•  $\frac{2}{3}\times\frac{1}{2}$  

•  $\frac{2}{3}\times\frac{2}{1}$  

•  $\frac{3}{2}\times\frac{2}{1}$  

Multiple Choice

Rewrite as a multiplication problem:

 $\frac{5}{7}\div\frac{3}{4}$  

Remember - Keep, Change, Flip

•  $\frac{5}{7}\times\frac{4}{3}$  

•  $\frac{5}{7}\times\frac{3}{4}$  

•  $\frac{7}{5}\times\frac{4}{3}$  

Multiple Choice

Rewrite as a multiplication problem:

 $\frac{6}{7}\div5$  

Remember - Keep, Change, Flip

•  $\frac{6}{7}\times\frac{5}{1}$  

•  $\frac{6}{7\ }\times\frac{1}{5}$  

Multiple Choice

Rewrite as a multiplication problem:

 $\frac{3}{4}\div2\ \frac{1}{2}$  

Remember - Keep, Change, Flip

•  $\frac{3}{4}\times\frac{5}{2}$  

•  $\frac{3}{4}\times\frac{2}{5}$  

Now that you can find the reciprocal and rewrite division as multiplication, all you have to do is multiply!

Multiple Choice

• $\frac{6}{40}$

• $\frac{3}{4}$

• $\frac{1}{2}$

• $\frac{12}{20}$

Multiple Choice

Solve.

• $\frac{8}{9}$

• $\frac{1}{5}$

• 1

• $\frac{4}{5}$

Multiple Choice

 $\frac{1}{8}$   $\div$  3

• 3

•  $\frac{1}{24}$  

•  $\frac{3}{8}$  

•  $\frac{1}{8}$  

Multiple Choice

Solve:

 $\frac{1}{2}$    $\div$    1 $\frac{3}{4}$  

•  $\frac{7}{4}$  

•  $\frac{3}{8}$  

•  $\frac{4}{14}$  

• 5

Multiple Choice

¹/₄  ÷  ¹/₂

• ²/₆
• ¹/₈
• ³/₅
• ²/₄

Multiple Choice

What is the quotient of these fractions in lowest terms?

• 6/40
• 6/10
• 3/5
• 12/20

Let's Review

Multiple Choice

What is another word for "Flip"?

• Same

• Fraction

• Equal

• Reciprocal

Multiple Choice

What is the rule for Dividing Fractions?

• "Keep, Keep, Flip"

• "Keep, Change, Flip"

• "Keep, Change, Keep

• I don't know!

Multiple Choice

How do you divide fractions?

• Use "KCF" and divide

• Just divide the numerators then the denominators

• Multiply the fractions

• Use "KCF" then multiply the numerators and denominators

Poll

How do you feel about dividing fractions?

• Great

• Really Good

• Good

• Kinda Good

• Not Good