## Archive for March 2, 2012

### Ordered Pairs, Gumby, and Palindromes

My sons recently received green, flexible toys from their aunt. When I turned on my calculator today, it read:

(2, GUMBYS)

I’m not sure why it’s an ordered pair, but seeing that on my calculator screen cracked me up.

Then tonight at dinner, they made up their own knock-knock joke:

Knock, knock.
Who’s there?
Gumby.
Gumby who?
Gumby more fun to chew than anything else!

While I’m happy that my four-year-old sons have a sense of humor, it’s their love of math that I most appreciate. Yesterday in the car, Eli noted that the time was 6:16 p.m. “Palindrome!” he shouted.

“Actually,” Alex said, “any time that it’s six, colon, number, six, it’s a palindrome.”

“That’s right,” I said. “How many times a day do you think the time is a palindrome?”

Eli guessed 50. Alex guessed 70. But those were clearly random guesses. I asked if they could figure it out.

“We could count them,” Eli suggested.

“No,” Alex said. “An easier way is, ‘What is 24 × 6?'”

“Why would 24 × 6 give you the answer?” I asked, mainly because I was sure he didn’t know.

“Because there are 24 hours in a day,” he said, “and there are 6 times each hour — when the middle number is 0, 1, 2, 3, 4, or 5.” He then used the distributive property to calculate 24 × 6 = (20 + 4) × 6 = 120 + 24 = 144.

“No,” Eli said. “There aren’t 6 palindromes at 10 o’clock.”

They discussed it for a while, and they agreed that there was only one palindrome of the form 10:_1, 11:_1, and 12:_1. And using that piece of info, they jointly concluded that there are 18 hours in a day with 6 palindromes and 6 hours in a day with just 1 palindrome, giving a total of 114 palindromes per day.

Though none of them are as good as these:

One? No!
Six axis.
Seven eves.
Nine men in. (A palindrome about nine, with nine letters, and an allusion to baseball, which has nine players per team. Sweet!)
Tenet.

Some people love the smell of napalm in the morning, but I love listening to two kids solve a math problem. I may even love it more than I love a good Gumby joke!

The Math Jokes 4 Mathy Folks blog is an online extension to the book Math Jokes 4 Mathy Folks. The blog contains jokes submitted by readers, new jokes discovered by the author, details about speaking appearances and workshops, and other random bits of information that might be interesting to the strange folks who like math jokes.

## MJ4MF (offline version)

Math Jokes 4 Mathy Folks is available from Amazon, Borders, Barnes & Noble, NCTM, Robert D. Reed Publishers, and other purveyors of exceptional literature.