Some rates are expressed as a ratio of one fraction to another. Complex fractions—fractions whose numerator, denominator, or both are fractions—take the form , or . One way to find a unit rate for a rate that is a complex fraction is to find a common denominator for the fractions that make up the complex fraction and then complete the division. To better understand how this calculation works, let's look at an example. Selma uses a jogging trail that runs through a park near her home. The trail is a loop that is of a mile long. On Monday, Selma ran the loop in of an hour. What was Selma's unit rate in miles per hour for Monday's run? Next, you'll calculate Selma's unit rate in miles per hour using the common denominator method. Now, write Selma's jogging rate as a complex fraction. A complex fraction is one whose numerator, denominator, or both are fractions. Be sure to include units in your answer.