Ratio

• A ratio is a _________of ____ separate but related quantities. 

Ratios• Example:Ratio of Georgia fans to Alabama

fans15 Georgia fans and 20 Alabama

fans What is the ratio of GA fans to AL

fans?

• The _____ of the ratio is very important—whichever word comes first, the _____ must come first.

• ___:___

Notations for ratios• ____ different ways to write a ratio

• ___:____ ____notation• ___to___ ____notation• — ____notation

Describe these ratios.

1. 3:4 4. 3:7

2. 7 to 4 5. 7/3

3. 4/3 6. 4 to 7

• Ratios can be written to compare

______ to a part, a ______ to the

whole, or the whole to a ______.

Make your own ratios

Practice

• What if your ratio was 4:10—Florida wins to Georgia wins?

• In fraction form? —

• Since I can write my ratio as a _____, I can simplify it.

Equivalent Ratios• _______ ratios are ratios that name

the same ________.• You can find an equivalent ratio by

______ or ______ both terms of a ratio by the same number.

Now you try it: Write 3 equivalent ratios comparing

yoyo’s to bubbles.

You and your partner have 5 minutes to go find the following

ratios in the room.• Record both the original and

simplest form of the ratio.• 5 to 10 ⅞ • 11:12• Boys to girls adults to

kids

Proportions

• This is an example of a proportion.•

• A proportion is an ________ that shows two __________ ratios.

=

Examples of proportions

• One bag of puppy chow lasts 4 weeks.

• Two bags of puppy chow lasts 8 weeks.

• 1 bag = 2 bags 4 weeks 8 weeks

Ratio site practice• Let’s get started!