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Section 2.2: Rate, Unit Rate, and Unit Price Objectives: I can define what a rate, unit rate, unit price is. I can express rates, unit rates, and unit price using words and symbols. I can identify, describe, and record rates from reallife examples. I can solve problems using rates. Rate What is a rate? A rate is a comparison between two quantities measured in different units of measurement. What is an example of a rate? You ran 5 miles in 2 hours. A rate to represent you running would be 5 miles or 5 miles per 2 hours 2 hours 5 apples cost $2.00. A rate to represent the cost of the apples would be $2.00 5 apples REMEMBER – ALWAYS put money in the numerator! Notice: A rate can be written as a fraction only! Rate More examples of a rate? You paid $1.69 for a 100 gram of sugar. A rate to represent your case $1.69 or $1.69 per 100 gram 100 g Your heart beats 72 beats every one minute. A rate to represent your heart beating would be: 72 beats or 72 beats per minute min REMEMBER – ALWAYS put money in the numerator! Unit Rate What is a unit rate? A unit rate is a rate in which the second term is one . What is an example of a unit rate? You ran 20 km in one hour. A unit rate to represent you running is 20 km or 20 km per hour! h How do we find unit rate? 1st: Set up a unit rate 2nd: Divide by the denominator 3rd: Write your answer in word form (the numerator PER the denominator). Unit Rate Another example of a unit rate. A car drives 30 miles on 10 gallons. To write a unit rate follow the three step. 1st: Set up a rate 2nd: Divide by the denominator 3rd: Write in word form 30 miles 10 gallons 30 miles ÷ 10 = 3 miles 10 gallons ÷ 10 1 gallon 3 miles per gallon Unit Rate Your turn. Heba earns $78.00 for working 6 hours at Tim Hortons. Determine the unit rate for this situation. 1st: Set up a rate 2nd: Divide by the denominator 3rd: Write in word form $78.00 6 hr $78.00 ÷ 6 = $13.00 6 hr ÷ 6 1 hr $13.00 per hour Show You Know In your binder, do Show You Know questions on page 57. Show All your work! Answers: A) 6 m per 1 s B) $11 per 1 h C) $1.8 per can Remember the Key Words Rate: A rate is a comparison between two quantities measured in different units of measurement. Example: 100 words or 100 words per 5 min 5 min Unit Rate: A unit rate is a rate in which the second term is one . Example: 15 km or 15 km per 1 hour 1 hr Unit Price What is a unit price? A unit price is a unit rate that makes it easier to compare the cost of similar items. Often used when shopping Usually shown per 100g or 100 mL What is an example of a unit rate? Unit Price How do we find unit price? 1st: Set up a unit price formula. 2nd: Divide cost by the volume. 3rd: Write your answer in word form (the numerator PER the denominator). Homework Page 60 Questions: 4, 5, 6 Page 61 Questions: 10, 11, and 13