Solve.

1.Find the unit rate of a 12-oz bottle of orange juice that sells for $1.29.

2.A building is 1,275 feet tall. How many yards tall is this building?

10.75¢/oz.

Math on the Mind

425 yards

Dimensional Analysis

Unit 4, Lesson 10

Conversion Factors

• A conversion factor is a ratio of equivalent measurements.

Example Problem:A roll of Christmas gift wrap contains 2.5 meters of paper. What is the length of the paper in yards?

http://www2.franciscan.edu/academic/mathsci/mathscienceintegation/MathScienceIntegation-620.htm

Example Problem:A roll of Christmas gift wrap contains 2.5 meters of paper. What is the length of the paper in yards?

Step 1:    Find the conversion factor that gives a ratio between meters and yards.

Conversion factor    

1 meter = 1.09 yards

http://www2.franciscan.edu/academic/mathsci/mathscienceintegation/MathScienceIntegation-620.htm

Example Problem:A roll of Christmas gift wrap contains 2.5 meters of paper. What is the length of the paper in yards?

Step 2: Write the conversion factor as a fraction with the unit you wantwant to convert to on top and set the problem up as a proportion.

http://www2.franciscan.edu/academic/mathsci/mathscienceintegation/MathScienceIntegation-620.htm

2.5 meters x  1.09 yards  =    1 meter2.725 yards

Using Conversion Factors

Practice:

Practice:

The fastest recorded speed for an eastern gray

kangaroo is 40 mi per hour. What is the

kangaroo’s speed in feet per second?

40 mi1 h

5280 ft1 mi

1 h 60 min

1 min60 s

• • •

The kangaroo’s speed is about 58.7 ft/s.

= 58.6 ft/s

Example:

Customary Units

• http://www.brainpop.com/math/numbersandoperations/customaryunits/preview.weml

http://www.hillsboroschools.net/team6a/connor/math/Ch3%20--%20Decimals%20and%20Metrics/MeasurementPics/units_of_measure.gif