Question about Regression Equations

I'm working on an assignment using Minitab and the last question is giving me some trouble.

We have a list of data regarding states and their percentages of exercise and diabetes.

The question is as follows:

For the regression using exercise as the predictor variable (X) and diabetes as the predicted variable (Y), if 25% of respondents for a certain state reported that they exercised 3 or more times a week, what would the regression equation predict would be the % of respondents that report having been diagnosed with diabetes?

I can assume the teacher wants an actual % and not just an estimation (like the people diagnosed with diabetes would decrease). But I'm not sure how to solve this (using an equation or just using Minitab).

Thanks!

EDIT: Okay so I figured out that I need to put numbers back into the regression equation. Which is Y= -.2522x + 15.22

I assume I put 3 in for x but I have no idea where the 25% comes in.

HALLLP.