Ratios and Unit Rates
Name
Chapter 11, Lesson 2B
Objective: To understand and describe a ratio relationship and unit rates
You can write a ratio to describe how two numbers are related.
A ratio that compares two unlike quantities is called a rate.
A clothing store purchaser orders large shirts and medium shirts
at a rate of 3 : 2. What does this ratio show?
The ratio, 3 to 2, shows the rate at which the number of large shirts were
ordered to the number of medium shirts. This means that for every
3 large shirts ordered 2 medium shirts were also ordered.
A ratio that is simplified to have a denominator of 1 unit is called a unit rate.
A car travels an average of 100 miles every 2 hours.
Find the unit rate of distance traveled in miles to the time in hours.
r The ratio or rate is 100 miles : 2 hours.
100 miles
r Rewrite as a fraction. _______
2 hours
r Simplify to get a denominator of 1.
distance traveled in miles
time in hours
Think
The car travels
50 miles every
hour.
Copyright © by William H. Sadlier, Inc. All rights reserved.
100 miles ! ______
50 miles
_______
2 hours
1 hour
50 miles .
So, the unit rate is 50 miles per hour or ______
1 hour
Practice
Write a ratio for the situation. Then find the unit rate.
2. A mixture has 2 parts oil to 1 part water.
1. A store charges $3 for every 12 oranges.
ratio:
ratio:
unit rate:
unit rate:
3. There are 120 students for every
4 classrooms.
4. Jackie can type 182 words for every
4 minutes while writing a report.
ratio:
ratio:
unit rate:
unit rate:
Discuss and Write
5. Use a ratio of oranges to dollars to describe the situation in exercise 1.
What is the unit rate using this ratio? What does this unit rate mean?
Grade 6, Lesson 11-2B
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239
2/12/13 1:09 PM
Ratios and Unit Rates
Name
Chapter 11, Lesson 2B
Practice
Explain what the ratio means.
6. A trail mix recipe uses ounces of nuts and
raisins in a ratio of 5 : 3.
7. Chaperones are needed for students on
a field trip in a ratio of 2 : 12.
Write a ratio for the situation. Then find the unit rate.
9. Luke travels 6 miles for every 45 minutes
8. Katie spends $12 for every 80 tiles.
he runs.
ratio:
ratio:
unit rate:
unit rate:
10. A drama club earns $375 for every 30 play tickets sold.
11. A restaurant needs 30 pounds of fish for
every 40 customers.
ratio:
ratio:
unit rate:
unit rate:
Find the unit rate. Then answer the question.
12. Jenna pays $12 for every 2 dozen bagels.
How much would she pay for 8 bagels?
13. Jesse’s car can travel 264 miles for every
12 gallons of gas. How far can the car
travel using 5 gallons of gas?
14. Noel is making lemonade for a party. She
uses 4 scoops of mix for every 2 quarts of
water. The container of mix has 18 scoops.
How much mix is left after making 5 quarts
of lemonade?
15. A soccer league has 108 players for every
6 teams. The league has 3 fields to use for
games. If each team has the same number
of players, how many players are there in
all on 9 teams?
Copyright © by William H. Sadlier, Inc. All rights reserved.
Problem Solving
Explain Your Reasoning
$15
3 lunches both describe the relationship
16. The ratios _______
and _______
3 lunches
$15
between the total cost and the number of friends who go to lunch.
How can you use one of the ratios to find the cost of 8 lunches?
240 Grade 6, Lesson 11-2B
5106-6_WB06_240 240
For additional Practice, go to page 284 in this Workbook.
Then go to Lesson 11-3, pages 380–381 in the Student Book.
2/12/13 1:09 PM