You drive from your house to the dry cleaners, which is 12 miles east of your house. You then drive to the grocery store from the dry cleaners. The grocery store is 15 miles west of your house. What distance did you cover?

39 miles

Explanation:

we will make your house to be the central point in the four cardinal points.

Please follow the diagram on the attachment to get the movement clearly.

First, you move to a dry cleaners 12miles east of your house, and then to a grocery store 15miles west of your house.

This means you must have moved back to your house before going to the grocery which is 15miles west of your house.

so to and fro from your house to dry cleaners = 12*2 = 24 miles.

Then the total distance you cover will be = 24 +15 = 39 miles