1. 2.5 What is a Rate? Mme DiMarco

2.  Learning Goal: in this lesson, you will learn what a rate is and how to apply your knowledge in problem solving. Learning Goal

3.  When we compare two different things, we have a rate  We need 5 sandwiches for every 2 people  Oranges are on sale at $1.49 for 12  Gina earns $4.75 per hour for babysitting (unit rate)  There are 500 sheets on one roll of paper towel (unit rate)  Unit rate: the quantity associated with a single unit of another quantity  Example: 6 metres per 1 second (6m/s) What is a rate??

4.  The doctor took Marjorie’s pulse. He counted 25 beats in 20 seconds. What is Marjorie’s heart rate in beats per minute? Problem

5.  The doctor took Marjorie’s pulse. He counted 25 beats in 20 seconds. What is Marjorie’s heart rate in beats per minute?  There are 25 beats in 20 seconds  There are 60 seconds in 1 minute  25 beats / 20 seconds  x beats / 60 seconds  25 beats (x 3) / 20 (x 3)  75 beats / minute Solution In order to make 20 to 60, we multiply by 3; what we do to one side of the rate, we do to both sides

6.  A printing press prints 120 sheets in 3 minutes. a)Express the printing as a rate b)How many sheets are printed in 1 hour? c)How long will it take to print 1000 sheets? Problem

7.  A printing press prints 120 sheets in 3 minutes. a)Express the printing as a rate b)How many sheets are printed in 1 hour? c)How long will it take to print 1000 sheets?  The printing press prints 120 sheets in 3 minutes  So, in 1 minute the printing press prints:  120 ÷ 3 / 3 ÷ 3  40 / 1  The rate of printing is 40 sheets / minute Solution

8.  A printing press prints 120 sheets in 3 minutes. a)Express the printing as a rate b)How many sheets are printed in 1 hour? c)How long will it take to print 1000 sheets?  The printing press prints 40 sheets / minute  One hour is 60 minutes  40 x 60 / 1 x 60  2400 sheets / 60 minutes  2400 sheets / hour  The printing press prints 2400 sheets / hour Solution

9.  A printing press prints 120 sheets in 3 minutes. a)Express the printing as a rate b)How many sheets are printed in 1 hour? c)How long will it take to print 1000 sheets?  The printing press prints 40 sheets / 1 minute  If we want to find out how many minutes it will take to reach 1000 sheets, we use division  1000 ÷ 40 = 25  It will take 25 minutes to print 1000 sheets Solution

10.  Page 64, #1 – 5, 7, 8 Homework