2.2 Rates

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Section 2.2:
Rate, Unit Rate, and Unit Price
Objectives:
 I can define what a rate, unit rate, unit price is.
 I can express rates, unit rates, and unit price using
words and symbols.
 I can identify, describe, and record rates from reallife examples.
 I can solve problems using rates.
Rate
 What is a rate?
 A rate is a comparison between two quantities measured in
different units of measurement.
 What is an example of a rate?
 You ran 5 miles in 2 hours. A rate to represent you running
would be 5 miles
or
5 miles per 2 hours
2 hours
 5 apples cost $2.00. A rate to represent the cost of the apples
would be $2.00
5 apples
 REMEMBER – ALWAYS put money in the numerator!
 Notice: A rate can be written as a fraction only!
Rate
 More examples of a rate?
 You paid $1.69 for a 100 gram of sugar. A rate to represent
your case $1.69
or
$1.69 per 100 gram
100 g
 Your heart beats 72 beats every one minute. A rate to
represent your heart beating would be:
72 beats
or
72 beats per minute
min
 REMEMBER – ALWAYS put money in the numerator!
Unit Rate
 What is a unit rate?
 A unit rate is a rate in which the second term is one .
 What is an example of a unit rate?
 You ran 20 km in one hour. A unit rate to represent you
running is 20 km
or
20 km per hour!
h
 How do we find unit rate?
 1st: Set up a unit rate
 2nd: Divide by the denominator
 3rd: Write your answer in word form (the numerator PER the
denominator).
Unit Rate
 Another example of a unit rate.
 A car drives 30 miles on 10 gallons. To write a unit rate follow
the three step.
 1st:
Set up a rate

2nd: Divide by the denominator

3rd: Write in word form
30 miles
10 gallons
30 miles ÷ 10 = 3 miles
10 gallons ÷ 10
1 gallon
3 miles per gallon
Unit Rate
 Your turn.
 Heba earns $78.00 for working 6 hours at Tim Hortons.
Determine the unit rate for this situation.
 1st:
Set up a rate

2nd: Divide by the denominator

3rd: Write in word form
$78.00
6 hr
$78.00 ÷ 6 = $13.00
6 hr ÷ 6
1 hr
$13.00 per hour
Show You Know
 In your binder, do Show You Know questions on





page 57.
Show All your work!
Answers:
A) 6 m per 1 s
B) $11 per 1 h
C) $1.8 per can
Remember the Key Words
 Rate:
 A rate is a comparison between two quantities measured in
different units of measurement.
 Example: 100 words
or 100 words per 5 min
5 min
 Unit Rate:
 A unit rate is a rate in which the second term is one .
 Example: 15 km
or
15 km per 1 hour
1 hr
Unit Price
 What is a unit price?
 A unit price is a unit rate that
makes it easier to compare
the cost of similar items.
 Often used when shopping
 Usually shown per 100g or
100 mL
 What is an example of a
unit rate?
Unit Price
 How do we find unit price?
 1st: Set up a unit price formula.

2nd: Divide cost by the volume.

3rd: Write your answer in word form (the numerator PER the
denominator).
Homework
 Page 60
 Questions: 4, 5, 6
 Page 61
 Questions: 10, 11, and 13
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