Lesson 11 Ratios Rates and Percents Motion Rates

Lesson 11 Ratios, Rates and Percents Motion Rates

Warm-Up 1. Stan runs at a rate of 7 miles in 1 hour. Pat runs at a rate of 9 miles in 1. 5 hours. Which person runs at a faster rate? 2. A local berry farm charges $3. 00 for 4 pounds of berries. How much will it cost to buy 12 pounds of berries at the local farm?

Motion Rates Target: Solve problems, compare and convert motion rates.

Vocabulary � Motion � Rate: A rate that compares distance to time. Conversion: A process of changing at least one unit of measurement in a rate to a different unit of measurement.

Example 1 Oksana’s family traveled on a highway through central Oregon at a rate of 60 miles per hour. Her family traveled at this rate for 2. 5 hours. How far did they drive? � Locate the unit rate. � Multiply � Oksana’s by 2. 5 hours. 60 miles per hour 60 × 2. 5 = 150 family traveled 150 miles in 2. 5 hours.

Example 2 Wayne and Marla each left home on their bikes. They were meeting at the library, which is exactly the same distance from each of their homes. Wayne traveled at a rate of 20 miles every 2 hours. Marla traveled at a rate of 6 miles every 0. 5 hour. They left at the same time. Who arrived at the library first? � Find Wayne’s unit rate of speed. � Find Marla’s unit rate of speed. � Marla rode faster, so she arrived at the library first.

Converting Rates 1. Write the rate as a fraction. 2. Identify the units you want in the answer. 3. Multiply the original rate by a conversion rate using equivalent measurements. Make sure the unwanted units cancel to get the answer.

Example 3 Convert 4 miles per hour to feet per hour. � Write the rate as fraction. � Identify � Fill units in answer. in conversion rate. � Multiply. � 4 miles per hour = 21, 120 feet per hour

Example 4 Convert 3 feet per minute to feet per hour. � Write the rate as fraction. � Identify units in answer. � Fill in conversion rate. � Multiply. � 3 feet per minute = 180 feet per hour

Exit Problems 1. Michael rode his bike at a rate of 10 miles per hour. If he rode at this rate for 3 hours, how far did he ride? 2. Identify the faster rate: or 3. Convert 3 miles per hour to feet per hour.

Communication Prompt � Suppose you walk to school at a rate of 4 miles per hour. How can you convert this rate to feet per hour? OR � Think of as many conversion rates as possible. Write the conversion rates in a list.