Ratios & Proportions

​Ratios & Proportions

By Phoenix Ward

Ratio, Rates, Unit Rates, proportions & Percent Proportions

Ratios

• Must be written as the question asked when comparing 2 quantities

• Must be simplified, but left as a comparison of the quantities

• Ratios have many equivalent forms and a ratio table is a great visual to see those equivalent forms

Multiple Choice

There are 7 ushers and 11 technicians helping at the Harper Middle School fall play. What is the ratio of technicians to all helpers?

• 7:11

• 11:7

• 11:18

• 18:11

Multiple Choice

Which number will complete the equivalent ratio for 4:12?

20:_____

• 60

• 48

• 12

• 2

Multiple Choice

What is an equivalent ratio for 5 dogs to 3 cats?

• 15 to 9

• 10 to 9

• 9 to 15

• 9 to 10

Unit Rates

• Are rates simplified to 1

• Always you to compare similar rates when you know the value of 1

• Easier to manage in fraction form with a denominator of 1

Multiple Choice

An eight pack of juice boxes costs $4.79, and a 12 pack of juice boxes cost $7.59. Use this information to calculate the better buy.

• 8 boxes

• 12 boxes

• Neither

Multiple Choice

Fruit Loops at 17 ounces for $3.68 or Apple Jacks at $2.89 for 13 oz , which is the better buy?

• Apple Jacks

• Fruit Loops

• Neither

Proportions

• Are two equivalent ratios

• Use to find missing parts of an equivalent ratio

• Need to be set up with LABELS - ALWAYS

• Part to Part, Part to whole or whole to part- READ THE QUESTION, before setting up your proportion

Multiple Choice

The ratio of a quarterback's completed passes to attempted passes is 7 to 8. If he attempted 24 passes, how many did he complete?

• 21

• 3

• 8

• 27

Multiple Choice

It takes Emma 18 minutes to type and spell check 14 pages of manuscript. How long will it take her to type and spell check 77 pages?

• 18

• 60

• 99

• 1,386

Multiple Choice

If a car travels 280 miles in 7 hours, how far will it travel in 12 hours?

• 480

• 84

• 25

• 1,960

Converting decimal ratios into fractions

Multiple Choice

Convert 8.4 : 3.9 into a fraction.

• 24/11
• 32/15
• 16/7
• 28/13

Multiple Choice

Convert .855 : .950 into a fraction

• 8/10
• 7/10
• 9/10
• 6/10

Percent Proportions

• Always Part to whole

• You need to know that a whole percent is 100%- NEVER given in story

• Set up proportion with LABELS - ALWAYS

• Remember the part percent REPRESENTS the same thing as the part.

Convert Decimals to Fractions & Mixed Numbers

6.4G

Multiple Choice

What is 0.73 written as a fraction?

• 73/100
• 37/50
• 7/10
• 73/10

Multiple Choice

Change to a fraction:

0.391

• 391/1000

• 391/100

• 3/91

• 391