A runner ran 25 miles last week and 15 miles this week. What is the percent of change

40%

Step-by-step explanation:

The change in percent is the difference of the two distances ran divided by the last week's distance and the result multiplied by 100%

That's

25 - 15 / 25 x 100%

10/25 x 100%

0.4 x 100%

40%

The percentage change 40%

21.25 or 28.75