Lesson 1 Proportionality Measurement

Warm-Up Complete each conversion. 1 foot = _____ inches 1 yard = _____ feet 1 meter = _____ centimeters 1 kilometer = _____ meters 1 day = _____ hours 1 minute = _____ seconds 1 pound = _____ ounces 1 gallon = _____ quarts

Target: Convert customary and metric measurements.

Vocabulary Conversion: The process of renaming a measurement using different units.

Example 1abc Determine the unit of measurement you should use in each situation. a. dimensions of a room in your house feet b. time until school is over hours or minutes c. distance from home to your nearest mall miles or kilometers

Example 1de Determine the unit of measurement you should use in each situation. d. amount of milk to buy for a family at the store gallons or quarts e. angle to cut flooring in a bathroom degrees

Example 2 Choose a reasonable estimate. Explain each choice. a. length of a pen: 10 cm or 10 m 10 cm. One meter is about the length of a yard stick. b. distance to school on a bus: 20 m or 20 km 20 km. You would not ride the bus 20 m (that’s about 60 feet). c. amount of juice in a juice box: 1 pint or 1 gallon 1 pint. A gallon of juice is much to large.

Unit Conversions When converting from a larger unit to a smaller unit, MULTIPLY ( × ). When converting from a smaller unit to a larger unit, DIVIDE ( ÷ ).

Example 3ab Complete each conversion. a. 4 yards = ___ feet Find the conversion factor. 1 yard = 3 feet Yards are larger units, multiply. 4(3) = 12 4 yards = 12 feet b. 48 ounces = ___ pounds Find the conversion factor. 1 pound = 16 ounces Ounces are smaller units, divide. 48 ÷ 16 = 3 48 ounces = 3 pounds

Example 3c Complete each conversion. c. 3 hours = ___ minutes Find the conversion factor. 1 hour = 60 minutes Hours are larger units, multiply. 3(60) = 180 3 hours = 180 minutes

Example 4 Convert 4 kilometers to centimeters. First convert 4 km to meters, then to centimeters. Find the conversion factor for km to m: 1 kilometer = 1000 meters Kilometers are larger units, multiply. 4(1000) = 4000 4 kilometers = 4,000 meters Find the conversion factor for m to cm: 1 meter = 100 centimeters Meters are larger units, multiply. 4000(100) = 400,000 4 kilometers = 400,000 centimeters

Example 5 The second highest waterfall in Oregon is Salt Creek Falls in the Cascade Mountain Range. It is 286 feet tall. Find its height in: a. inches. b. yards. a. Find the conversion factor. 1 foot = 12 inches Feet are larger units, multiply. 286(12) = 3432 Salt Creek Falls is 3,432 inches tall. b. Find the conversion factor. 1 yard = 3 feet Feet are smaller units, divide. 286 ÷ 3 ≈ 95.3 Salt Creek Falls is about 95.3 yards tall.

Exit Problems Complete each conversion: 40 meters = _____ centimeters 120 minutes = _____ hours 4 tons = _____ pounds

Communication Prompt What is a real-world situation where you would need to convert measurements?