Cruisin' to Grandma's House
RAY: Here's the answer. This young gal didn't calculate the average speed; she calculated the average of the speeds.
TOM: Yes, a common mistake.
RAY: In fact, her average speed is not 50 miles an hour but 48 miles an hour. And you arrive at that by calculating the total distance divided by the total time. The total distance being 240 miles, and the total time being 5 hours.
TOM: So 240 divided by 5...
RAY: Which comes out to be 48 miles an hour. Who's our winner?
TOM: The winner is Herbert Nelson from Chicago, Illinois. Congratulations, Herbert!
[ Car Talk Puzzler ]