1. Warm Up Divide. Round answers to the nearest tenth. 1. 2. 3. 4. 23.3 3.5 23.8 23.9 420 18 73 21 380 16 430 18

2. Vocabulary Rate Unit Rate Unit Price Estimate

3. Ratio: 90 3 Rate: 90 miles 3 hours...as a ratio like this, A rate is a comparison of two quantities measured in different units. For example, the phrase “90 miles per 3 hours” can be written......or as a rate, like this

4. Unit rates are rates in which the second quantity is 1. unit rate: 30 miles, 1 hour or 30 mi/h The ratio 90 3 can also be simplified by dividing: 90 3 = 30 1

5. Class Example Geoff can type 30 words in half a minute. How many words can he type in 1 minute? Write as a rate. = Geoff can type 60 words in one minute. Multiply to find words per minute. 60 words 1 minute 30 words minute 1212 30 words 2 minute 2 1212

6. Partner Practice Penelope can type 90 words in 2 minutes. How many words can she type in 1 minute? 90 words 2 minutes Write a rate. = Penelope can type 45 words in one minute. 90 words ÷ 2 2 minutes ÷ 2 Divide to find words per minute. 45 words 1 minute

7. Individual Practice A piece of gold with a volume of 0.5 cubic meters weighs 9650 kilograms. What is the density of gold? Gold has a density of 19,300 kg/m 3. 9650 kg 0.5 m 3 Write the rate. Multiply to find kilograms per 1 m 3. 9650 kg 2 0.5 m 3 2 19,300 kg 1 m 3

8. To estimate is to find a value that is close to the actual value, but not necessarily the true value.

9. Estimate the unit rate. Partner Practice 313 Is not divisible by 8, so choose a number close to 313 that is divisible by 8. 313 feet in 8 seconds 313 feet to 8 seconds is approximately 40 feet per second.  313 feet 8 seconds 320 feet 8 seconds  40 feet 1 second Divide to find feet per second.

10. Estimate each unit rate. Individual Practice Choose a number close to 583 that is divisible by 85. 583 soccer players to 85 soccer balls. 583 soccer players to 85 soccer balls is approximately 7 players per soccer ball.  583 players 85 soccer balls 595 players 85 soccer balls  7 players 1 soccer ball Divide to find players per soccer ball.

11. Unit price is a unit rate used to compare price per item.

12. Pens can be purchased in a 5-pack for $1.95 or a 15-pack for $6.20. Which pack has the lower unit price? Class Practice Set up proportions for both situations. price for package number of pens = $1.95 5 =$0.39 price for package number of pens = $6.20 15  $0.41 The 5-pack for $1.95 has the lower unit price. Divide the price by the number of pens. Compare to determine your answer.

13. Jamie can buy a 15 oz jar of peanut butter for $2.19 or a 20 oz jar for $2.78. Which jar has the lower unit price? Partner Practice  $2.19 15 = $0.15 = $2.78 20  $0.14 The 20 oz jar for $2.78 has the lower unit price. price for jar number of ounces price for jar number of ounces