Rates: The Rate Formula And Unit Conversion, Continued

Now solve the following rate problem on your own.

Select the correct answer and then click Continue.

The correct answer choice will be the number of miles the runner ran in the third interval. Therefore, we are solving for distance:

According to the question stem, the runner's pace decreased by 2 miles per hour in each 10-minute interval after the first interval. Her average rate during the first interval was 13 miles per hour. Her average rate during the third interval is then: 13 – 2 – 2 = 13 – 4 = 9 miles per hour.

And, since we are asked to solve for the third 10-minute interval, time is equal to 10 minutes:

miles = rate time = 9 m/p/h 10

Converting minutes to hours, we find:

Choice (C) is correct.