7-2 Rates 7-2 Rates (p. 292-295)(p. 292-295)

Indicator- Indicator-

M1 M1 Select appropriate units for derived Select appropriate units for derived measurementsmeasurements

7-2 Rates 7-2 Rates p. 292-295p. 292-295

A A raterate is a ratio of two measurements with is a ratio of two measurements with different units. different units.

Unit ratesUnit rates are ratios with a denominator of 1. are ratios with a denominator of 1.

(Unit rates give an equal basis for (Unit rates give an equal basis for comparison, and have many real-life comparison, and have many real-life applications, such as miles per hour, price applications, such as miles per hour, price per unit of weight, and calories per serving.) per unit of weight, and calories per serving.)

To convert a ratio to a To convert a ratio to a unitunit rate, divide the rate, divide the numerator and denominator of the ratio by the numerator and denominator of the ratio by the number in the denominator.number in the denominator.

Express each rate as a unit rate. (Denominator of 1) Express each rate as a unit rate. (Denominator of 1)

1) $50 for 10 days1) $50 for 10 days 2) 8 revolutions in 2 minutes2) 8 revolutions in 2 minutes

10

50$

days

1010

1050

1

5

2

8

minsrevolution

22

28

1

4

The unit rate is $5 per day. There are 4 revolutions per minute.

In a bike race, Tariq rode 42 km in 2 In a bike race, Tariq rode 42 km in 2 hours. What was his unit rate? hours. What was his unit rate?

Write the rate as a fraction.Write the rate as a fraction.

Find the equivalent rate with a Find the equivalent rate with a denominator denominator of 1. (The GCF of 42 & 2 is 2.) of 1. (The GCF of 42 & 2 is 2.)

Write a sentence.Write a sentence.

Tariq rode at a rate of 21 km per hourTariq rode at a rate of 21 km per hour..

1

21

Population densityPopulation density is the number of people per is the number of people per square mile. What is the population density of square mile. What is the population density of a town with a population of 5,250 and an area a town with a population of 5,250 and an area of 5 square miles?of 5 square miles?

Write the rate as a fraction.Write the rate as a fraction. Find the equivalent rate with a Find the equivalent rate with a

denominator denominator of 1. (GCF) of 1. (GCF)

Write a sentence.Write a sentence.

5

250,5

.

MileSq

People

1

050,1

The town’s population density is 1,050 people per square mile.

HomeworkHomework

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