Unit Rate

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Unit Rate Review
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Vocabulary Review

• A ratio is a comparison of two quantities by
  division.
• 17 out of 20 students, or
• A rate is a special type of ratio comparing two
  quantities with different units.
• Driving 120 miles in 2 hours, or
• A unit rate is a rate that is simplified so that
  it has a denominator of 1 unit.
• Driving 120 miles in 2 hours, or

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Example 1 Andy biked 24 miles in 4 hours. If
he traveled at a constant speed, how many miles
did he ride in 1 hour?
Write a verbal model of what you are comparing.
Substitute in the values given for each quantity.
Since a unit rate has a denominator of 1 unit,
divide the numerator and denominator by 4.
Andy biked 6 miles per hour.
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Example 2 A 12-pack of Gatorade costs 13.44.
What is the unit price per bottle?
Write a verbal model of what you are comparing.
Substitute in the values given for each quantity.
Divide the numerator and denominator by 12 to
find the unit rate.
The unit price is 1.12 per bottle.
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Example 3 The price of three different bags of
cat food are shown in the table to the right.
Which bag has the lowest price per pound?
Cat Food Prices Cat Food Prices
Size of bag (lbs) Price ()
3.5 4.83
7 9.45
20 27.20
Write a verbal model of what you are comparing.
For the 3.5 lb bag,
For the 7 lb bag,
For the 20 lb bag,
The 7 pound bag is the least expensive at 1.35
per pound
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Example 4 After 3.5 hours, Peyton had traveled
161miles. If she travels at a constant speed,
how far will she have traveled in 4 hours?
Write a verbal model of what you are comparing.
Find the unit rate in miles per hour.
Multiply the unit rate, or average speed, by the
number of hours traveled.
Peyton travels 184 miles in 4 hours.
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Example 5 Jerry can jog 1? miles in ¼ hour.
Find his average speed in miles per hour.
Write a verbal model of what you are comparing.
Substitute in the values given for each quantity.
Since average speed in miles per 1 hour, divide
the numerator and denominator by ¼ .
Jerry jogs at an average speed of 5 ? miles per
hour.
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Example 6 Mr. Isaacs is spreading mulch in his
yard. He spreads 4? square yards in 2 hours.
How many square yards can he mulch in 1 hour?
Write a verbal model of what you are comparing.
Substitute in the values given for each quantity.
Divide the numerator and denominator by 2 to find
the unit rate.
Mr. Isaacs can mulch 2 ? square yards per hour.