A rate is a ratio that compares two related quantities. Common rates are speed = \({distance \over time}\), flow = \({amount \over time}\), and defect = \({errors \over units}\).
What is the distance in miles of a trip that takes 1 hour at an average speed of 15 miles per hour?
| 420 miles | |
| 15 miles | |
| 630 miles | |
| 120 miles |