A rate is a ratio that compares two quantities expressed in different kinds of units.
- 3 pens cost $1.19. Items (pens) are one kind of unit and money ($1.19) is another.
- A jet may travel at the rate of 1,000 miles per hour. Distance (miles) is one kind of unit and time (hour) is another.
- The speed of light in space is 186,000 miles per second. Distance (miles) is one kind of unit and time (second) is another.
- The rate of interest on a loan for a new car was advertised as 5.9% per year. This is a complex kind of rate. It comares a rate (percent, or parts per hundred) with another kind of unit, time (year).
See also interest, unit price.