Search Header Logo
  1. Resource Library
  2. Math
  3. Fractions
  4. Multiplying And Dividing Fractions
  5. Multiplying And Dividing Fractions
Multiplying and Dividing Fractions

Multiplying and Dividing Fractions

Assessment

Presentation

Mathematics

4th - 7th Grade

Easy

CCSS
6.NS.A.1, 5.NF.B.6, 4.NF.B.4A

+1

Standards-aligned

Created by

Brian Lemoi

Used 997+ times

FREE Resource

4 Slides • 10 Questions

1

Multiplying and Dividing Fractions

Slide image

2

Multiplying Fractions

This is the easy one. If fact, you've already done it when you were adding fractions and finding a common denominator.


When multiplying fractions, just multiply straight across. Numerator times numerator. Denominator times denominator. That's it.



Slide image

3

Multiple Choice

 12×45\frac{1}{2}\times\frac{4}{5}  

1

 410\frac{4}{10}  

2

 57\frac{5}{7}  

4

Multiple Choice

 35(23)\frac{3}{5}\left(\frac{2}{3}\right)  

1

 58\frac{5}{8}  

2

 615\frac{6}{15}  

5

Multiple Choice

 12(12)\frac{1}{2}\left(\frac{1}{2}\right)  

1

 12\frac{1}{2}  

2

 14\frac{1}{4}  

3

 24\frac{2}{4}  

6

Multiple Choice

What's the rule for multiplying fractions?

1

Just multiply straight across.

2

Keep, Change, Flip

3

You must have a common denominator

7

Poll

How do you feel about multiplying fractions?

Great (it's pretty easy)

Horrible (I'm so lost)

Eh... it's okay.

8

Dividing Fractions

Rule#1 for Dividing Fractions: DON'T DIVIDE.


Instead of dividing you do this procedure:


KEEP, CHANGE, FLIP

Slide image

9

Dividing Fractions

So lets look closely at this:


 23÷45\frac{2}{3}\div\frac{4}{5}  Don't divide. Instead, keep

 the  23\frac{2}{3}  , change the  ÷\div   to   ×\times   

and flip the  45\frac{4}{5}   so that it's  54\frac{5}{4}  .

Now just multiply.  23×54=1012\frac{2}{3}\times\frac{5}{4}=\frac{10}{12}  

Slide image

10

Multiple Choice


After I "Keep, Change, Flip" what equation would I have?

 12÷25\frac{1}{2}\div\frac{2}{5}  

1

 21×25\frac{2}{1}\times\frac{2}{5}  

2

 12×52\frac{1}{2}\times\frac{5}{2}  

11

Multiple Choice


Solve

 12÷25\frac{1}{2}\div\frac{2}{5}  

1

 45\frac{4}{5}  

2

 54\frac{5}{4}  

3

 210\frac{2}{10}  

12

Multiple Choice

Solve:

 110÷23\frac{1}{10}\div\frac{2}{3}  

1

 320\frac{3}{20}  

2

 230\frac{2}{30}  

13

Multiple Choice

Solve

 34÷12\frac{3}{4}\div\frac{1}{2}  

1

 54\frac{5}{4}  

2

 38\frac{3}{8}  

3

 64\frac{6}{4}  

14

Multiple Choice

When dividing fractions, what rule do we use?

1

Keep, Change, Flip

2

Multiply straight across

3

Must have a common denominator

Multiplying and Dividing Fractions

Slide image

Show answer

Auto Play

Slide 1 / 14

SLIDE