Unit Rate – Outschool

Unit Rate Lesson

I. The Basics

Unit rate is the amount of something there is for every unit of something else. For example, if you are driving 50 miles per hour, you are covering 50 miles during each hour.

To find the unit rate, simply divide:

Example 1: You paid $10 for 4 cups of coffee. What is the price per cup of coffee?

Divide $10 by 4 cups of coffee to get [latex]10div4[/latex] = $2.50 per cup of coffee.

II. Comparing Unit Rates

Example 2: You can either buy 25 pounds of dog food for $15.49 or 55 pounds for $34.99. Which option is a better deal and by how much?

Find the unit rate (price per pound) for each option by dividing the price by the number of pounds:

Option A: $[latex]15.49div25[/latex] pounds = $0.62 per pound

Option B: $[latex]34.99div55[/latex] pounds = $0.64 per pound

Option A has a lower unit rate, so it is the better deal by $0.64 – $0.62 = $0.02 per pound.

II. Unit Rate Applications

Example 3: You are renting a photo booth for a party. The rental company charges $350 for the first 3 hours, then $225 per hour for any additional hours. How much will it cost to rent the photo booth for 6.5 hours?

The cost for the first 3 hours is $350.

After the first 3 hours, you need 3.5 more hours (6.5 total) at a unit rate of $225 per hour. The total cost for the 3.5 additional hours is ($225 per hour)·(3.5 hours) = $787.50.

Total, it will cost you $350 + $787.50 = $1137.50 to rent a photo booth for 6.5 hours.

Unit Rate Quiz