- By
**limei** - Follow User

- 65 Views
- Uploaded on

Download Presentation
## PowerPoint Slideshow about ' 5 Minute Check' - limei

**An Image/Link below is provided (as is) to download presentation**

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

Multiply Fractions

Objective: To understand how to multiply fractions.

Multiply Fractions

At the end of this lesson you should be able to answer the following question.

If two positive fractions are less than one, why is the product also less than one?

Multiply Fractions

To multiply fractions, multiply the numerators and multiply the denominators, then simplify if needed.

Example x =

32 63

4 x 5 = 20 = 10

x =

Multiply Fractions

Multiply.

13

2 x 5=

Estimate?

Reminder – When estimating the product of two fractions, round each fraction to 0, ½ or 1 and then multiply.

Multiply Fractions and Whole Numbers

Multiply.

13

2 x 5=

Actual Product?

133

2 x 5= 10

31

Is this a reasonable answer? 10 ≈ 4

Multiply Fractions

Multiply.

25

3 x 6 =

Actual Product?

25105

3 x 6 = 18 = 9

Is this a reasonable answer?

Multiply Fractions

Multiply.

25

3 x 6 =

Actual Product?

25105

3 x 6 = 18 = 9

51

Is this a reasonable answer? 9 ≈ 2

Multiply Fractions

If the numerators and denominators have a common factor you can simplify before multiplying.

Multiply Fractions

If the numerators and denominators have a common factor you can simplify before multiplying.

Example

25

3 x 6 =

All numbers are prime factors (which means they have no factors other than one and itself), except for 6. What are the factors of 6?

Multiply Fractions

If the numerators and denominators have a common factor you can simplify before multiplying.

Example

25

3 x 6 =

25

3 x2 x 3 =

Are there any factors that appear in the numerator and denominator?

Multiply Fractions

If the numerators and denominators have a common factor you can simplify before multiplying.

Example

25

3 x 6 =

25

3 x2 x 3 =

2 the common to both

Multiply Fractions

If the numerators and denominators have a common factor you can simplify before multiplying.

Example

25

3 x 6 =

25 5

3 x2 x 3 = 9

We can cancel the both 2’s.

Multiply Fractions

Frank had ½ of the lawn left to mow. On Saturday he mowed 2/3 of what was left. What fraction of the lawn did he mow on Saturday?

Do this on your own.

Multiply Fractions

Frank had ½ of the lawn left to mow. On Saturday he mowed 2/3 of what was left. What fraction of the lawn did he mow on Saturday?

122 1

2x 3= 6 = 3

Multiply Fractions

A paint store has 35 gallons of paint in storage, 2/5 of which are for outdoor use. The others are for indoor use. If each gallon costs $22, what is the total cost of the indoor paint in storage?

Do this on your own.

Multiply Fractions

A paint store has 35 gallons of paint in storage, 2/5 of which are for outdoor use. The others are for indoor use. If each gallon costs $22, what is the total cost of the indoor paint in storage?

There is a couple of different ways to solve this problem.

If 2/5 is outdoor paint, what fraction is indoor paint?

Multiply Fractions

A paint store has 35 gallons of paint in storage, 2/5 of which are for outdoor use. The others are for indoor use. If each gallon costs $22, what is the total cost of the indoor paint in storage?

If 2/5 is outdoor paint, what fraction is indoor paint?3/5

What is 3/5 of 35 gallons?

Multiply Fractions A paint store has 35 gallons of paint in storage, 2/5 of which are for outdoor use. The others are for indoor use. If each gallon costs $22, what is the total cost of the indoor paint in storage?

If 2/5 is outdoor paint, what fraction is indoor paint? 3/5

What is 3/5 of 35 gallons?

335105

5 x 1 = 5 =21

What is the cost of 21 gallons?

Multiply Fractions A paint store has 35 gallons of paint in storage, 2/5 of which are for outdoor use. The others are for indoor use. If each gallon costs $22, what is the total cost of the indoor paint in storage?

What is the cost of 21 gallons?

21 x $22 = $462

Multiply Fractions

If two positive fractions are less than one, why is the product also less than one?

Multiply Fractions

Agenda Notes

Homework –

Homework Practice 4-3

Show all Work

Due Thursday, Oct 24

Mid Chapter 4 Quiz –Monday, Oct 28

Download Presentation

Connecting to Server..