This equation is a matter of doing addition and subtraction in the right order. You start with 14.6, because that is how far he is away from his home. Then, you subtract 9.8 because he's coming towards his home, and he is now 4.8 miles away from his home. Finally add 5.3 because he runs away this time, and you end up with Bob is 10.1 miles away from his home. Guess he'd better start running back!