Statistics Definitions > Ratios and Rates

**Contents (click to skip to that section):**

## Ratio Definition

A ratio is a comparison of two numbers. It can be written in many ways. For example, the ratio of 5 to 9 can be expressed as:

- 5 to 9
- 5 out of 9
- 5:9
- 5/9

## Rate Definition

A **rate **is a specific type of ratio that *usually *tells you how long it takes to do something. For example, a rate might be 100 miles / 10 hours. In simple English, that’s saying it takes 10 hours to travel 100 miles. We can reduce that fraction to a “per hour” statement (by using the greatest common factor or another similar method); simplifying, it becomes 10 miles per hour.

**In most cases**, a rate will have **time **in the denominator and is a measure of how long it takes to do something; the numerator will also have different units from the denominator, as in the above example. However, there are exceptions in common usage (like “tax rates” and “interest rates”), which have the same units and measure “something else” like interest charged per amount loaned.

## References

Doctor Peterson. Rate vs. Ratio. Article posted on The Math Forum. Retrieved June 2, 2018.

------------------------------------------------------------------------------**Need help with a homework or test question? **With Chegg Study, you can get step-by-step solutions to your questions from an expert in the field. Your first 30 minutes with a Chegg tutor is free!

*Statistical concepts explained visually* - Includes many concepts such as sample size, hypothesis tests, or logistic regression, explained by Stephanie Glen, founder of StatisticsHowTo.

**Comments? Need to post a correction?** Please post a comment on our *Facebook page*.