A magic trick

I was standing on the street corner with Domino and a group of schoolkids came up. “Hey, can I show you a magic trick?” one of them asked.

“Uh…”

“Think of a number,” he said.

“Ok.”

“Now add 4 to it.”

“Ok.”

“Now add 5 to it.”

“Ok.”

“Now add 1 to it.”

“Ok.”

“Now subtract your original number from it.”

“Ok.”

“Did you get 10?”

“Nope!”

“What? What number did you choose?”

“I was using a different base. If you’re using base 16, then 4, 5, and 1 don’t add up to 10. Don’t kid a kidder, kid.” Then I flipped him a nickel and his head exploded with the power of math.

Well, not really. I wish I had the presence of mind to do that. But next time an elementary school kid tries that, I’m so ready.