1. 8-5 6 th grade math Rates

2. Objective To use rates to solve problems Why? To know how to convert miles per hour, miles per gallon, revolutions per minute, $ per hour, $ per pound, etc.

3. California State Standards AF 2.2 : Demonstrate an understanding that rate is a measure of one quantity per unit of value of another quantity. NS 1.2 : Interpret and use ratios in different contexts … to show the relative sizes of two quantities, using appropriate notations (x/y, x to y, x : y) NS 1.3 : Use proportions to solve problems … AF 2.3: Solve problems involving rates, average speed, distance, and time. MR 1.1: Analyze problems by identifying relationships…

4. Vocabulary Rate – A ratio that compares different kinds of units 25 feet in 3 hours, 5 cans of peaches for $2, etc. Unit – Meaning 1 (uni = 1) 1 teacher, 1 box of Kleenex, etc. Unit rate – A ratio that compares a quantity to a unit of one 8 1/3 feet per hour, $0.40 per can, etc. Per – Each or divide Miles per hour = mi/hr

5. How to Solve Rates 1)Write a proportion a)First ratio is using the known rate b)Second ratio is placing an unknown value in numerator and 1 in the denominator 2) Solve by cross multiplying. 3) Check for reasonableness Traveled 99 miles in 90 minutes. What is average rate of speed in miles per hour? 99 = x 1.5 1 99 ÷ 1.5 = 66 mph Or 99 = x 90 1 (99 ÷ 90) x 60 = 66 mph

6. Who scored more points? R = 72 pts in 8 games B = 57 pts in 6 games 72 / 8 = 9 pts per game 57 / 6 = 9.5 pts per game B scored more pts per game

7. Try It! Find the unit rate. 1)90 miles in 75 minutes 2)252 miles every 9 gallons 3)48 chairs for 6 tables 4)96 students in 3 classrooms 1)1.2 miles per minute 2)28 miles per gallon 3)8 chairs per table 4)32 students per classroom

8. Objective Review To use rates to solve problems Why? You now know how to convert miles per hour, miles per gallon, revolutions per minute, $ per hour, $ per pound, etc. A rate is a special ratio involving two quantities with different units, such as miles per hour. Miles per hour = miles/hour = miles ÷ hour

9. Independent Practice Complete problems 6- 10 Copy original problem first. Show all work! If time, complete Mixed Review: 12-18 If still more time, work on Accelerated Math.