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WHAT DOES RATE MEAN? A rate is a RATIO that compares two things that have DIFFERENT units! Ex: Students per Bus OR Miles per Hour The unit rate is the rate for one unit of a given quantity. Unit rates have a denominator of 1. The word PER means 1 !!!! GOING FROM RATE TO UNIT RATE 150 heartbeats in 2 minutes Rate: 150 heartbeats See how there 2 minutes are 2 different units of measure? just DIVIDE to get the Unit Rate!!! 150 ÷ 2 = 75 heartbeats per minute. You can also write it as… 75 heartbeats / minute FIND THE UNIT RATE Amy can read 88 pages in 4 hours. What is the unit rate? (How many pages can she read per hour?) 88 ÷ 4 = 22 88 pages 4 hours So… 1 hr Notice that hours turns to 1…that is the number you divide by! 22 pages per hour or 22 pgs / hr NOT ALL RATES WILL BE EVEN NUMBERS! It is $30 for 4 t-shirts. What is the unit rate? $30 4 shirts 30 ÷ 4 = 7.5 1 shirt You have to add a decimal and a zero!! How much $ is this? $7.50 for each shirt! SOMETIMES YOU KNOW THE UNIT RATE ALREADY… Joe’s car goes 20 miles per gallon of gasoline. How far can it go on 8 gallons of gasoline? *Per Means 1. Here’s what it looks like! x8 20 miles 1 gallon = 8 gallons x8 20 x 8 = 160. Joe’s car can go 160 miles on 8 gallons of gas. SOMETIMES YOU KNOW THE UNIT RATE ALREADY… It costs $15.50 per student for the trip. If there are 20 students going, how much will the total be? *Per Means 1. Here’s what it looks like! x 20 $15.50 1 student = 20 students x 20 15.50 x 20 = 310. So it will cost $310 for 20 students to go. It’s easy to remember: If you need to FIND a UNIT rate, you DIVIDE If you already KNOW the Unit Rate, you MULTIPLY If you are ever unsure WHICH number to divide by, find the measure that will become a 1. This measure is what you divide by!!!