New beware of the rug--MPH

A small child’s voice piping from the back seat of car: “Why are there 25 Mr. Potato Heads?”
Grandma: “Mr. Potato Heads?”
Small child: “Yes, 25 M P H”
Mother from front seat of car: “That would be Miles Per Hour, but it was quite logical of you to think Mr. Potato Heads. It means the speed limit is 25 miles per hour not that there are 25 Mr. Potato Heads.”
Small child: “Oh.”