Tim: All right, give me another problem.
Mark: OK. "Bill's car goes 40 miles per hour. Mary's car goes 60 miles per hour. How long will it take for each of them to go 120 miles?"
Tim: All right. What size motors do they have?
Mark: What?
Tim: Is it automatic or manual transmission? That's got to make a difference.
Mark: Dad!
Randy: The answer is Bill, three hours, Mary, two.
Mark: Thanks.
Tim: I shouldn't be helping you with your math homework anyway.
Mark: You're not.