A runner can run 3 miles in 30 minutes. how long will it take to run 2.5

25 minutes.

Step-by-step explanation:

We can set up an equation: 3/30=2.5/n. This situation is directly proportional, since the number of minutes increases as the runner runs more miles.

We can cross multiply: 3n=30*2.5

3n=75

n=25