1 / 15

Ratios and Rates

Ratios and Rates. Section 5.1 & 5.2. Objectives:. Solve problems involving average speed, distance, and time. (AF 4.2) Choose an appropriate unit measure and use ratios to convert within and between measurement systems. (MG 1.0) Compare measures within and between measurement items

lamis
Télécharger la présentation

Ratios and Rates

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Ratios and Rates Section 5.1 & 5.2

  2. Objectives: • Solve problems involving average speed, distance, and time. (AF 4.2) • Choose an appropriate unit measure and use ratios to convert within and between measurement systems. (MG 1.0) • Compare measures within and between measurement items (MG 1.1)

  3. Words to know ~ • Ratio – a comparison of a number “a” and a nonzero number “b” using division. Example – 12 games to 7 games ; 12 to 7; 12:7 • Rate – a type of ratio that comparestwo • quantities that have different kinds of units of measure. Example – 100 miles in 2 hours • - 6 pencils for $1.40

  4. Writing a Ratio • Voting – Barack Obama won 333 electoral votes while John McCain won 156. What’s the ratio of Obama’s votes to McCain’s votes? • Ratio – Obama votes = McCain votes 333 156 111 = 52 Ratio can be written also as 111:52 , or “111 to 52”

  5. Rewriting with the same units • A map shows the distance between the classroom and the bathroom as 16 inches. In reality, the distance is 4 yards. 16 in 16 inches 144 in 4 yards x 36 MUST CONVERT TO THE SAME UNIT OF MEASURE!!! 1 in = 9 in

  6. Finding a Rate • You and your family drove 400 miles in 8 hours. • What was the average rate of speed? 50 miles 400 miles 1 hour 8 hours Reduce the numbers.

  7. Summary: Ratio is …. Rate is ….

  8. Finding a Unit Rate • A 6 pack of soda costs $1.60. A 12 pack of soda costs $ 3.00. Which is the better buy? $1.60 $0.27 = 1 can 6 cans $3.00 $0.25 = 12 cans 1 can Better buy - 12 pack

  9. Finding a Unit Rate Golf balls can be purchased in a 3-pack for $4.95 or a 12-pack for $18.95. Which pack has the lower unit price? price for package number of balls $4.95 3 =  $1.65 price for package number of balls $18.95 12  = $1.58 The 12-pack for $18.95 has the lower unit price.

  10. price for bottle number of ounces price for bottle number of ounces John can buy a 24 oz bottle of ketchup for $2.19 or a 36 oz bottle for $3.79. Which bottle has the lower unit price? Finding a Unit Rate $2.19 24 =  $0.09 $3.79 36 =  $0.11 The 24 oz jar for $2.19 has the lower unit price.

  11. Practice Identify if the problems are rates or ratios. 1.) 3.) 210 hits 240 feet rate rate 30 seconds 165 games 2.) 76 players ratio ratio 4.) 90 inches 144 players 30 feet

  12. Practice • Write each fraction in simplest terms. 3 inch 1 pint 8 pints 36 in. 1.) 3.) 16 pints 4 ft 4 inch 2 pints 1 hour 12 hours 2.) 6 hours 3 days

  13. Summary • Remember thata ratiois a comparison of two numbers. Example = number of A’s compared to the number of B’s • Remember that a rate is a type of ratio that compares two quantities that have different kinds of units of measure. • Example = 2 pairs of pants for $25. (comparing the number of pants to the dollar amount.)

  14. 30 7 1 2 Lesson Quiz Write each ratio in simplest form. 1. 22 tigers to 44 lions 2. 5 feet to 14 inches 3. Meka can make 6 bracelets per half hour. How many bracelets can she make per hour? 12 Estimate each unit rate. 4. $2.22 for 6 stamps 5. 8 heartbeats in 6 seconds $0.37 per stamp 1.3 beats/s Find each unit price. Then tell which has the lower unit price. 6. A half dozen carnations for $4.75 or a dozen for $9.24 7. 4 pens for $5.16 or a ten-pack for $12.90. a dozen They cost the same.

  15. Activity • Using the grocery store flyers (with a partner), create 3 rates and 3 ratios. • Exchange them with another team. • Solve the other team’s rates and ratios.

More Related