Quick Intro to Ratios

Ratio

A comparison of two numbers using division

You can write a ratio in 3 different forms: fraction, colon, the word "to"

You can use a ratio to compare information in three different settings: a part-to-part comparison, a part-to-whole comparison, or a whole-to-part comparison

Multiple Select

What are the 3 ways you can write a ratio?

• fraction

• colon between two numbers

• use the word "to"

• upside down

Part to Part Ratios

A Part to Part Ratio is when you compare one part to another part.

For example, "10 girls and 8 boys" is part to part because you are comparing part of the classroom to another part.

Part to Whole Ratios

A Part to Whole Ratio is when you compare one part to the total amount.

For example, "10 girls and 18 students" is part to whole because you are comparing part of the classroom to the total amount of students.

Multiple Choice

What type of ratio is this?

7 girls to 5 boys

• part-to-part

• part-to-whole

• whole-to-part

Multiple Choice

What type of ratio is this?

7 girls to all the students in the class

• part-to-part

• part-to-whole

• whole-to-part

Multiple Choice

What type of ratio is this?

all the students in the class to 5 boys

• whole-to-part

• part-to-part

• part-to-whole