Lesson Objective
The lesson is aligned to the Common Core State Standards for Mathematics – 6.RP.3.b Ratios and Proportional Relationships – Solve unit rate problems including those involving unit pricing and constant speed.
Materials Required
Calculator
Lesson Procedure
Using unit rate to solve real world and mathematical problems.
To solve unit rate problems, a teacher organized a one-minute contest for the students in her class. The challenges in the contest are foot tapping, eye blinking and finger snapping.
- During the foot tapping challenge, Alice tapped her foot 30 times in 15 seconds. At this rate, how many times could Alice tap her foot in 1 minute (60 seconds)? At what rate was Alice tapping her foot (taps per second)?
- Peter tapped his foot 48 times in 30 seconds. At this rate, how many times could Peter tap his foot in 1 minute (60 seconds)? At what rate was Peter tapping his foot (taps per second)?
- During the eye blinking challenge, Sandra blinked her eyes 12 times in 10 seconds. At this rate, how many times could Sandra blink her eyes in 1 minute (60 seconds)? At what rate was Sandra blinking her eyes (blinks per second)?
- James blinked his eyes 18 times in 20 seconds. At this rate, how many times could James blink his eyes in 1 minute (60 seconds)? At what rate was James blinking his eyes (blinks per second)?
Answers
- Alice could tap her foot 120 times in 1 minute (60 seconds). A rate of 2 taps per second and can be written as 2:1.
- Peter could tap his foot 96 times in 1 minute (60 seconds). A rate of 1.6 taps per second and can be written as 1.6:1.
- Sandra could blink her eyes 72 times in 1 minute (60 seconds). A rate of 1.2 blinks per second can be written as 1.2:1.
- James could blink his eyes 54 times in 1 minute (60 seconds). A rate of 0.9 blinks per second and can be written as 0.9:1.
Individual or Group Work
Join the contest with a group of friends. Count the number of times each of you can snap your fingers in 10 seconds. Complete the table by recording your name in the first column and in the second column the number of times each of you snapped your fingers in 10 seconds. In the third column of the table show, at that rate, how many times you could snap your fingers in 1 minute and the rate written as snaps:second.
Solve the Unit Rate Problems
- 3 pounds of peaches cost $6. How many pounds of peaches could be bought for $24?
- 2 cantaloupes cost $5. How much would 6 cantaloupes cost?
- 1 pound of tomatoes cost $2.99. How much would 4 pounds cost?
- 2 watermelons cost $8. How many watermelons could be bought for $16?
- A 2-pound container of blueberries cost $5.00. At that rate, what would be the cost of a 1-pound container of blueberries?
- 10 mangos cost $10. What is the unit cost for the mangos?
- A 16-ounce container of strawberries cost $3.20. What is the unit cost for 1 ounce of strawberries?
- A pineapple cost $2.99. How much would 3 pineapples cost?
Answers
- 12 pounds of peaches
- $15
- $11.96
- 4 watermelons
- $2.50
- $1
- $0.20
- $8.97
Concluding Statement
Students should be able to solve unit rate problems including those involving constant speed and unit pricing.
This post is part of the series: Ratios, Rates and Percentages
- Using the Language of Ratio
- Using the Language of Rate
- Using Ratio and Rate
- Solving Unit Rate Problems
- Solving Problems Using Percent
- Converting Measurement Units