ALGEBRA READINESS LESSON 6-2 Warm Up Lesson 6-2 Warm-Up

ALGEBRA READINESS LESSON 6-2 Warm Up Lesson 6-2 Warm-Up

ALGEBRA READINESS “Rates” (6-2) What is a “rate”? What is a “unit rate”? Rate: a ratio that compares two quantities measured in different units. Example: is read as “120 miles ‘per’ or ‘each’ 4 hours” Unit Rate: the rate in which the denominator is 1 (rate ‘per’ 1 unit of a given quantity) - Unit rate is used in everyday life to determine the best value. It can be found by simplifying the fraction to a denominator of “1” or simply dividing the numerator (top number) by the denominator (bottom number). Example: = or 120  4 = 30 mph The above unit rate is read as “30 miles ‘per’ hour” (30 m/h or 30 mph) 120 miles 4 hours 120 miles 4 hours  4 30 miles 1 hours

ALGEBRA READINESS Find the unit rate for typing 145 words in 5 minutes. = 29 words/minute Divide. number of words number of minutes 145 words 5 minutes = Write a rate comparing words to minutes. The unit rate is 29 words per minute. Rates LESSON 6-2 Additional Examples

ALGEBRA READINESS A brand of apple juice costs $1.56 for 48 oz. Find the unit rate. The unit rate is 3.25¢ / oz. cost$1.56 ounces48 oz = 1.56  48 = = $0.325 / oz. or 3.25 ¢ per oz. Rates LESSON 6-2 Additional Examples

ALGEBRA READINESS “Rates” (6-2) How can you use unit rate to solve a problem? Once you know the unit rate (per 1 unit of a given quantity), you can use equivalent ratios to solve problems in which one of the numbers in the rate has changed. Example: A car travels about 30 miles per gallon of gasoline. About how far can the car travel on 8 gallons? Change the denominator (gallons) to 8 and use equivalent fractions (1 x ? = 8; since you multiplied the bottom by 8, multiply the top by 8 to find an equivalent ratio) The car can travel 240 miles on 8 gallons of gas.

ALGEBRA READINESS Apples cost $1.49 for 1 pound. How much do 5 pounds of apples cost? Write the unit rate. Then find an equal ratio. Five pounds of apples cost $7.45. Multiply each term by 5. $ pound $ pounds =  5 5  5 5 Rates LESSON 6-2 Additional Examples

ALGEBRA READINESS The same brand of pretzels comes in two sizes: a 10-ounce bag for $.99, and an 18-ounce bag for $1.49. Which size is a better buy? Round each unit cost to the nearest cent. Divide to find the unit cost for each size. The 18-ounce bag has the lower unit cost. It is the better buy. $ oz $.10 per ounce $ oz $.08 per ounce Rates LESSON 6-2 Additional Examples

ALGEBRA READINESS Find the unit rate for each situation in. in 3 years 2. 9 calls in 3 min 3. Carli walked 16 miles in 5 hours. Find the unit rate. 4. A 21-oz bottle of shampoo costs $2.80. A 12-oz bottle costs $1.35. Which bottle is the better buy? 6 in. per yr3 calls per min 3.2 mi/h 12-oz bottle Rates LESSON 6-2 Lesson Quiz