Warm Up

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Warm Up
Problem of the Day
Lesson Presentation
Lesson Quizzes
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Warm Up Find each unit rate. 1. jump rope 192
times in 6 minutes 2. four pounds of bananas for
2.36 3. 16 anchor bolts for 18.56 4. 288
movies on 9 shelves
32 jumps/min
0.59/lb
1.16/bolt
32 movies/shelf
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Problem of the Day The sum of four consecutive
integers is 182. What are the four numbers?
44, 45, 46, and 47
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Sunshine State Standards
MA.7.G.4.4 Compare, contrast, and convert units
of measure between different measurement systems
(US customary or metric (SI)), dimensions, and
derived units to solve problems.
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Vocabulary
unit conversion factor
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A unit conversion factor is a fraction in which
the numerator and denominator represent the same
quantity in different units.
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Additional Example 1 Using Conversion Factors to
Solve Problems
The average American uses 580 pounds of paper per
year. Find this rate in pounds per month, to the
nearest tenth.
The problem gives the ratio 580 pounds to 1 year
and asks for an answer in pounds per month.
Multiply the ratio by the conversion factor.
Divide 580 by 12.
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Check It Out Example 1
Sam drives his car 23,040 miles per year. Find
this rate in the number of miles driven per
month, to the nearest mile.
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Additional Example 2 Converting Between Metric
and Customary Units
One mile is about 1.6 kilometers. What is the
length in miles of a 10 kilometer race? Round to
the nearest tenth of a mile.
Write a proportion using 1 mi. 1.6 km.
miles kilometers

The cross products are equal.
1 10 1.6 x
Multiply.
10 1.6x
___ ___ 1.6 1.6
Divide each side by 1.6.
6.25 x
A 10 kilometer race is about 6.3 miles.
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Check It Out Example 2A
One inch is equal to 2.54 centimeters. How many
inches are there in 12 centimeters? Round to the
nearest tenth.
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Check It Out Example 2B
One gallon is equal to about 3.875 liters. How
many liters are there in 6 gallons? Round to the
nearest tenth.
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Additional Example 3 Application
A tennis pro serves a ball that travels the
length of the court, 78 feet, in 0.75 second. How
fast is the ball moving in feet per second? Check
your answer for reasonableness.
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Additional Example 3 Continued
The balls speed is 104 ft/s.
Convert ft/s to mi/h to see if the answer is
reasonable.
The balls average speed is 71 mi/h, which is a
reasonable speed for a serve.
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Check It Out Example 3
Gary travels 1,320 ft in 1.5 min on his bicycle.
How fast is he traveling in feet per min? Check
your answer for reasonableness.
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Check It Out Example 3 Continued
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Lesson Quizzes
Standard Lesson Quiz
Lesson Quiz for Student Response Systems
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Lesson Quiz
Find the appropriate factor for each
conversion. 1. You drive 136 miles from your
house to your aunts house at the lake. You use 8
gallons of gas. How many yards does your car get
to the gallon? 2. One ounce is about 28.3
grams. A box of cereal has a mass of 400 grams.
What is the weight of the box in ounces? Round to
the nearest tenth of an ounce.
29,920 yd gal
14.1 oz
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Lesson Quiz
Find the appropriate factor for each
conversion. 3. A cheetah was timed running 200
yards in 6 seconds. What was the average speed in
miles per hour?
68 mi/h
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Lesson Quiz for Student Response Systems
1. A recipe for lemonade requires diluting the
lemonade concentrate with 6 quarts of water. How
many gallons of water are required to dilute the
concentrate? A. 1 gallon B. 1.5 gallons C. 2
gallons D. 2.5 gallons
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Lesson Quiz for Student Response Systems
2. There are about 400 jelly beans in a pound.
There are 2.2 pounds in a kilogram. About how
many grams does a jelly bean weigh? A. 0.85 g B.
0.98 g C. 1.06 g D. 1.14 g
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Lesson Quiz for Student Response Systems
3. A sea horse swims at about 0.01 miles per
hour. What is the swim speed in inches per
second? A. 10.56 inches per second B. 10.75
inches per second C. 11.24 inches per second D.
11.5 inches per second