Unit Rates
Part of the Decimals, Percents & Ratios section of Coddy's Pre-Algebra journey. Lesson 42 of 56.
A rate compares two amounts measured in different units: kilometres and hours, dollars and kilograms, pages and minutes. A car drives 120 km in 2 hours. Its rate is 120 km per 2 hours.
A unit rate is the amount for ONE of the second unit. To find it, divide: 120 / 2 is 60, so the car drives 60 km per hour, written 60 km/h. The word per means for each, and the division shares the distance equally over the hours.
Why bother? Unit rates are easy to compare. A cyclist who rides 45 km in 3 hours goes 45 / 3, which is 15 km/h. Comparing 60 with 15 takes one glance; comparing 120 in 2 with 45 in 3 does not.
Challenge
A train travels 150 km in 3 hours. Its speed in km per hour is the unit rate on the board. Work it out and press Check.
Try it yourself
Simplify the expression
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Decimals, Percents & Ratios
4Dividing Decimals
Dividing by a DecimalDividing by 10 and 100Dividing by a Whole NumberUnit PriceRecap: Dividing