Bell Work: Simplify: (1) (10) -2

Answer: 100

LESSON 64: USING A UNIT MULTIPLIER TO CONVERT A RATE

A rate, such as 60 miles per hour, can be written in fraction form. 60 miles 1 hour We can use a unit multiplier to convert a rate to a different unit such as miles per minute. In this case, we would convert hours to minutes. Since 60 minutes equal 1 hour, we have these two unit multipliers available. 60 minutes 1 hour 1 hour 60 minutes

We choose the unit multiplier that cancels hours. 60 miles x 1 hour 1 hour 60 min. 60 miles x 1 mile 60 min 1 min So 60 mph equals 1 mile per minute.

To convert rates to alternative units, we create a unit multiplier using the appropriate units. Then we multiply the rate by the appropriate unit multiplier to cancel the unit we want to eliminate and include the unit we want in the answer.

Example: Yasmine ran a mile in 6 minutes. Use a unit multiplier to find her average rate in miles per hour.

Answer: 1 mile/6 minutes 1 mile x 60 min = 60 mile = 10mile 6 min 1 hour 6 hour 1 hour Average rate is 10mph

Example: Driving at 60 mph, a car travel about how many kilometers in 2 hours? (1 mile is about 1.6 km.)

Answer: 60mile x 1.6 km = 96 km 1 hour 1 mile 1 hour d = 96 km x 2 hour 1 hour = 192 km

HW: Lesson 64 #1-25