Course Ratios, Rates, and Unit Rates 5-2 Rates, and Unit Rates Course 3 Warm Up Warm Up Problem of the Day Problem of the Day Lesson Presentation Lesson Presentation
Course Ratios, Rates, and Unit Rates Vocabulary rate unit rate unit price
Course Ratios, Rates, and Unit Rates Ratio: 90 3 Rate: 90 miles 3 hours Read as “90 miles per 3 hours.” A rate is a comparison of two quantities that have different units.
Course Ratios, Rates, and Unit Rates 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 be simplified by dividing: 90 3 = 30 1
Course Ratios, Rates, and Unit Rates Additional Example 1: Finding Unit Rates Fred can type 80 words in 4 minutes. How many words can he type in 1 minute? Write a rate. = Fred can type 20 words in one minute. Multiply to find words per minute. 20 words 1 minute 80 words 4 minute 80 words /4 4 minute / 4
Course Ratios, Rates, and Unit Rates Check It Out: Example 1 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
Course Ratios, Rates, and Unit Rates To express a ratio as a rate per unit, write the ratio as a fraction and then divide the numerator by the denominator. 395 miles in 5 hours = 79 miles per hour miles hours miles hours
Course Ratios, Rates, and Unit Rates Express each ratio as a rate. 5 inches of rain in 30 days = inch of rain per day 120 words in 3 minutes = 40 words per minute words per minute ÷ 5
Course Ratios, Rates, and Unit Rates Unit price is a unit rate used to compare price per item.
Course Ratios, Rates, and Unit Rates Pens can be purchased in a 5-pack for $1.95 or a 15-pack for $6.20. Which is the better buy? Additional Example 4A: Finding Unit Prices to Compare Costs Divide the price by the number of pens. price for package number of pens $ =$0.39 price for package number of pens = $ $0.41 The better buy is the 5-pack for $1.95.
Course Ratios, Rates, and Unit Rates Jamie can buy a 15-oz jar of peanut butter for $2.19 or a 20-oz jar for $2.78. Which is the better buy? Additional Example 4B: Finding Unit Prices to Compare Costs $ = $0.15 = $ $0.14 The better buy is the 20-oz jar for $2.78. price for jar number of ounces price for jar number of ounces Divide the price by the number of ounces.
Course Ratios, Rates, and Unit Rates Golf balls can be purchased in a 3-pack for $4.95 or a 12-pack for $ Which is the better buy? Check It Out: Example 4A Divide the price by the number of balls. price for package number of balls $ =$1.65 price for package number of balls = $ $1.58 The better buy is the 12-pack for $18.95.
Course Ratios, Rates, and Unit Rates Check It Out: Example 4B John can buy a 24 oz bottle of ketchup for $2.19 or a 36 oz bottle for $3.79. Which is the better buy? $ = $0.09 = $ $0.11 The better buy is the 24-oz jar for $2.19. price for bottle number of ounces price for bottles number of ounces Divide the price by the number of ounces.
Course Ratios, Rates, and Unit Rates 5. Bob typed 593 words in 4 minutes. How many words did Bob type per minute? 1. Jacob can buy a 32 oz bottle of BBQ sauce for $2.93 or a 36 oz bottle for $3.19. Which is the better buy? 2. John can buy a 8 pencils for $1.25 or a 12 pencils for $2.00. Which is the better buy? 3. Mary made $25.00 for working 7 hours at the mall. How much did Mary make per hour? 4. Lisa paid $ for 3 pair of jeans. What did Lisa pay for each pair of jeans? Try These!
Course Ratios, Rates, and Unit Rates / 4 minutes = words/minute 1.$2.93 / 32 = $0.09 (better buy) $3.19 / 36 = $ $1.25 / 8 = $0.16 (better buy) $2.00 / 12 = $ $25.00 / 7 hours = $3.57 / Hr 4. $ / 3 pair of jeans = $52.67 / jean Try These! Round to nearest hundredth