Ratio whose second term is 1.

The concept of unit rate is important, as it is sometimes necessary to convert a ratio to a unit rate when solving certain types of problems.

### Example

John travelled 200 km in 4 hours. If he maintained the same speed (a constant speed), what distance did he travel per hour?

The following proportion may be written : \(\dfrac{200}{4}\) = \(\dfrac{x}{1}\).

This proportion may then be used to find the solution to the problem, that is : \(x\) = 50 km.