Math Lessons

#2 Son has a quiz coming up in Math class, about the metric system. It seems that someone hadn't studied perhaps as much as he should have. The following lesson was overheard today, Chez Borepatch:

Me: So which is bigger, a Centimeter or a millimeter?

#2 Son: Uh, a millimeter?

Me: Nope. [discussion of meters, centimeters, and millimeters deleted to avoid driving away 80% of my traffic]

Me: Does that make sense?

#2 Son:

Me: OK, how about this: you remember when we shot the Glock, right? What cartridge does it take?

#2 Son: 9 millimeter.

Me: 9 is almost 10, right? So 9 millimeters is almost a centimeter. Actually, there is a 10 mm cartridge, which is a centimeter, and is very manly indeed. We can shoot it sometime, but you'll have to be ready for some pretty big recoil. So which round will have more recoil, a 10 mm or a 1 mm?

#2 Son: That's dumb, Dad - nobody makes a 1 mm cartridge. But the 10 mm would have more recoil.

Me: And what's another measure for 10 mm?

#2 Son: A centimeter!

Class dismissed. I think I'll tell this story to his math teacher. I hear teachers in the Boston suburbs groove on this sort of thing.