How do I solve this, and does it matter that he first drove west then east? Jack entered the freeway at exit 112. He drove west and got off at exit 225. Then he got back on and drove east to exit 59. His trip took 7 hours. Assuming that there was no extra distance traveled getting on and off the freeway, what was his average velocity?

I can subtract 112 from 225 and I get 113. Then 59 from 225 for 166. So he drove a total of 279 miles, but only ended up 53 miles east of where he started. If I divide 53 by 7, I get 7.57 miles per hour, but do I assume that east is positive and west is negative, or is the answer actually -7.57 per hour?

Or do I have it all wrong?