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8-1. Customary and Metric Measurements. Course 2. Warm Up. Problem of the Day. Lesson Presentation. 8-1. Customary and Metric Measurements. Course 2. Warm Up 1. How many days are in 1 week? 2. How many seconds are in 1 minute? 3. How many inches are in 1 foot?
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8-1 Customary and Metric Measurements Course 2 Warm Up Problem of the Day Lesson Presentation
8-1 Customary and Metric Measurements Course 2 Warm Up 1. How many days are in 1 week? 2. How many seconds are in 1 minute? 3. How many inches are in 1 foot? 4. How many hours are in 1 day? 5. How many inches are in 1 yard? 7 60 12 24 36
8-1 Customary and Metric Measurements Course 2 Problem of the Day It takes a driver about 3 4 second to begin breaking after seeing something on the road. How many feet does the car travel in that time if it is going 10 mi/h? 20 mi/h? 30 mi/h? 11 ft; 22 ft; 33 ft
8-1 Customary and Metric Measurements Course 2 Learn to convert measurements between the customary and metric systems.
8-1 Customary and Metric Measurements Course 2 Recall that a unit conversion factor is a fraction whose numerator and denominator represent the same quantity but in different units.
8-1 Customary and Metric Measurements There are 24 hours in 1 day, so the possible conversion factors are or . Choose the second factor so that the day units will cancel. 24 hr 1 day 1 day 24 hr Remember! 60 s = 1 min 60 min = 1 hr 24 hr = 1 day 365 days = 1 year Course 2 Additional Example 1: Converting Between Units of Time How many hours are there in 102 days? 24 hr 1 day 2,448 hr 1 102 days · = = 2,448 hr There are 2,448 hours in 102 days.
8-1 Customary and Metric Measurements There are 60 minutes in 1 hour, so the possible conversion factors are or . Choose the second factor so that the hour units will cancel. 60 min 1 hr 1 hr 60 min Course 2 Try This: Example 1 How many minutes are there in 12 hours? 60 min 1 hr 720 min 1 12 hours · = = 720 min There are 720 minutes in 12 hours.
8-1 Customary and Metric Measurements Course 2 We use two systems of measurement: customary and metric. The customary system is based on measurements from old English law, and the metric system is based on powers of ten. Each system has its own units.
8-1 Customary and Metric Measurements Course 2
8-1 Customary and Metric Measures Course 2 Additional Example 2: Making One-Step Unit Conversions Convert 2,500 centimeters to meters. There are 100 centimeters to 1 meter. 2,500 m 100 1 m 100 cm Use a unit conversion factor. 2,500 cm · = = 25 m So 2,500 centimeters is equal to 25 meters.
8-1 Customary and Metric Measures Course 2 Try This: Example 2 Convert 15 gallons to quarts. There are 4 quarts to 1 gallon. 4 qt 1 gal 60 qt 1 Use a unit conversion factor. 15 gal · = = 60 qt So 60 quarts is equal to 15 gallons.
8-1 Customary and Metric Measurements 1 Make a Plan Understand the Problem 2 Course 2 Additional Example 3:Problem Solving Application Joshua bought 32 pints of ice cream for the end-of-the-year class party. How many gallons of ice cream did he buy for the party? Rewrite the question as a statement: • Find the number of gallons in 32 pints. List the important information: •Joshua bought 32 pints of ice cream. Use conversion factors to convert pints to quarts and then quarts to gallons.
8-1 Customary and Metric Measurements 3 Solve 4 Course 2 1 qt 2 pt 32 gal 8 1 gal 4 qt Use two conversion factors. 32 pt · = · = 4 gal Since 32 pints is equal to 4 gallons, Joshua bought 4 gallons of ice cream for the party. Look Back A gallon is a greater unit than a pint, so the answer should be less than 32. So 4 is a reasonable answer.
8-1 Customary and Metric Measurements 1 Make a Plan Understand the Problem 2 Course 2 Insert Lesson Title Here Try This: Example 3 John ordered 24 gallons of soda for the concession stand. If it is dispensed in containers holding 1 cup, how many individual drinks will he be able to sell? Rewrite the question as a statement: • Find the number of cups in 24 gallons. List the important information: •Joshua has 24 gallons of soda. Use conversion factors to convert gallons to quarts and then quarts to pints to cups.
8-1 Customary and Metric Measurements 3 Solve 4 Course 2 Use three conversion factors. 4 qt 1 gal 2 pt 1 qt 2 c 1 pt 384 c 1 = 24 gal · · · = 384 c Since 15 gallons is equal to 384 cups, John had enough soda to sell 384 cups. Look Back A cup is much smaller than a gallon, so the answer should be considerably larger than 24. So 384 is a reasonable answer.
8-1 Customary and Metric Measurement Course 2 Insert Lesson Title Here Lesson Quiz 1. How many minutes are there in 5.5 hours? 2. How many seconds are in 2 hours? Convert. 3. 320 cm = ______ m 4. 64 oz = _______ lb 5. How many gallons of oil are needed to fill a 40-quart barrel? 330 min 7,200 s 3.2 4 10 gal