8-3 Proportions and Customary Measurement Course 1 Warm Up Warm Up Lesson Presentation Lesson Presentation Problem of the Day Problem of the Day
Warm Up Find the missing value in each proportion. 1. = 2. = 3. = 4. = x = 6 x = 25 x = 35 Course Proportions and Customary Measurement 4 1 __ 24 x __ x 30 __ __ x 40 __ 8 x __ x = 12
Problem of the Day There are 4 ounces in a gill. There are 4 gills in a pint. There are 8 pints in a gallon. How many ounces are the same as the total of 3 gallons, 3 pints, 3 gills, and 3 ounces? 447 Course Proportions and Customary Measurement
Learn to use proportions to make conversions within the customary system. Course Proportions and Customary Measurement
Course Proportions and Customary Measurement
Additional Example 1A: Using Proportions to Convert Measurements A. Sonja went hiking for 4 hours. For how many minutes did she go hiking? 4 hr x min ____ 1 hr 60 min _____ = 1 hour is 60 minutes. Write a proportion. Use a variable for the value you are trying to find. The cross products are equal.60 4 = 1 x 240 = x Sonja hiked for 240 minutes. Course Proportions and Customary Measurement
Additional Example 1B: Using Proportions to Convert Measurements B. Mr. Lee is 72 inches tall. Find his height in feet. x ft 72 in. ____ 1 ft 12 in ____ = 1 foot is 12 inches. Write a proportion. Use a variable for the value you are trying to find. The cross products are equal.12 x = 1 72 x is multiplied by 12.12x = 72 Mr. Lee is 6 feet tall. 12x 12 ___ ___ = Divide both sides by 12 to undo the multiplication. x = 6 Course Proportions and Customary Measurement
Additional Example 1C: Using Proportions to Convert Measurements C. Hunter used 56 cups of water to wash his car. How many gallons of water did he use? x gal 56 cups ______ 1 gal 16 cups _______ = 1 gallon is 16 cups. Write a proportion. Use a variable for the value you are trying to find. The cross products are equal.16 x = 1 56 x is multiplied by 16.16x = 56 Hunter used 3.5 gallons of water to wash his car. 16x 16 ___ ___ = Divide both sides by 16 to undo the multiplication. x = 3.5 Course Proportions and Customary Measurement
Try This: Example 1A A. Helga went biking for 3 hours. For how many minutes did she go biking? 3 hr x min ____ 1 hr 60 min _____ = 1 hour is 60 minutes. Write a proportion. Use a variable for the value you are trying to find. The cross products are equal.60 3 = 1 x 180 = x Helga biked for 180 minutes. Course Proportions and Customary Measurement
Try This: Example 1B B. Ms. Hagan is 60 inches tall. Find her height in feet. x ft 60 in. ____ 1 ft 12 in. ____ = 1 foot is 12 inches. Write a proportion. Use a variable for the value you are trying to find. The cross products are equal.12 x = 1 60 x is multiplied by 12.12x = 60 Ms. Hagan is 5 feet tall. 12x 12 ___ ___ = Divide both sides by 12 to undo the multiplication. x = 5 Course Proportions and Customary Measurement
Try This: Example 1C C. Seymour used 40 cups of water to wash his dog. How many gallons of water did he use? x gal 40 cups ______ 1 gal 16 cups _______ = 1 gallon is 16 cups. Write a proportion. Use a variable for the value you are trying to find. The cross products are equal.16 x = 1 40 x is multiplied by 16.16x = 40 Seymour used 2.5 gallons of water to wash his dog. 16x 16 ___ ___ = Divide both sides by 16 to undo the multiplication. x = 2.5 Course Proportions and Customary Measurement
Lesson Quiz Find the missing value. 1. in. = 6 yd pt = gal Compare. Write, or = oz 2 lb. 4. 7,920 ft 1.5 mi 5. If your family is going to take a 3-week vacation, how many days will you be gone? Insert Lesson Title Here > = 1 2 __ 21 days Course Proportions and Customary Measurement