6th Grade Math Textbook, Progress

Ratio

11-1

Each form is read as

“the ratio of a tob.”

A ratio is a way of comparing two numbers or

quantities, aand b, by division. The numbers,

aand b, are called the terms of the ratio.

A ratio can be written in three forms.

Word form: ato b

Ratio form: a: b

Fraction form:

You can write a ratio to compare two amounts—

a part to a part, a part to a whole, or the whole to a part.

The picture above shows the following ratios:

a

b

Use the bar graph. Write each ratio in three ways.

1. news magazines to sports magazines


2. home magazines to fashion magazines


3. all magazines to home magazines


4. sports and hobby magazines to all magazines

Number

Hobby

Home

Fashion

Sports

News

10 2 3 4 5

Magazines

Magazines at

Anita's Newsstand

You can simplify ratios by dividing 2 to 20

both terms by their greatest 2 
 2 to 20 
 2

common factor (GCF). 1 to 5 Simplify.

Type Comparisons Word Ratio Fraction

Form Form Form

part to part 3 to 5 3 : 5 

3

5



part to whole 2 to 10 2 : 10 

1

2

0



whole to part 10 to 3 10 : 3

10

3

the number of fashion magazines

to the number of news magazines

the number of sports magazines to

the total number of magazines

the total number of magazines to

the number of fashion magazines

Divide terms by 2.

1.2

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