Archive for December, 2013

6 Degrees of Bad Math Jokes

I once read an article that said, “To a greater or lesser degree, everything tastes like chicken.” Well, that’s true, but it’s also true that everything tastes like broccoli, to a greater or lesser degree. Carrots, to a greater degree; mint chocolate chip ice cream, to a lesser degree.

To a greater or lesser degree, some of the following jokes are funny.

What did the thermometer say to the graduated cylinder?

Thermometer and Cylinder

A scientist dropped a thermometer and a candle from the roof of a building. He observed that both objects reached the ground at the same time. Conclusion: A thermometer falls at the speed of light.

A doctor walks into a meeting, and a nurse asks why he has a rectal thermometer behind his ear. “Damn,” says the doctor, “some asshole has my pen!”

The star college football player was taking a math exam. The coach desperately needed him for the big game on Saturday, so the professor agreed to an oral exam.

“All right,” said the professor. “How many degrees are in a circle?”

“That depends,” said the boy. “How big is the circle?”

If you’re cold and there’s a right triangle nearby, stand in the corner opposite the hypotenuse. It’s always 90° over there.

The number you have dialed is imaginary. Please rotate your phone 90°, and try again.

December 27, 2013 at 10:00 pm 1 comment

Oreos, Ratios, and the Perfect Cookie

Okay, first things first. What do you call the following shape?


I call it a pill. My sons call it a racetrack. But is there a formal name for a shape formed by a rectangle with a semicircle attached to each end? If not, I feel like there should be. Place your suggestions in the Comments.

Until I hear a better suggestion, I’m gonna keep callin’ it a pill.

The following trivia question is the reason I ask.

How many pills appear around the circumference of the trademarked design on an Oreo® cookie?

What’s that, you say? You didn’t know that there were little pills along the edge of each wafer on an Oreo cookie? Then you, my friend, need to pay a little more attention.

Because there aren’t just some pills around the circumference. There are 96 of those little buggers, and each of them has a rectangle with a length-to-width ratio of approximately 3:2 between two semicircles.

See for yourself.

Oreo Design

Ironically, the ratio of 3:2 brings me to the main reason I’m writing today.

The original Oreo represented good design: a single layer of vanilla cream filling trapped between two crisp, chocolate wafers. But it always felt lacking to me. If only it had just a little more cream, then it would be perfect. A potential solution arrived in 1974, when Nabisco released the Double Stuf variety — two chocolate wafers with twice as much filling1 as its predecessor. Yet the Double Stuf teetered too far in the opposite direction. It was too sweet.

Which brings me to the delectable treat that I discovered today: the Triple Double Oreo, which is running a strong campaign for the title of World’s Best Cookie. My wife describes it as “the Big Mac of cookies.” Not two but three chocolate wafers with a thin layer of cream filling between each pair. And the pièce de résistance — one layer of vanilla cream filling, the other chocolate.

Now that’s what I call intelligent design.

Triple Double Oreo

It absolutely nails the ratio for wafer:filling.


Double Stuf

Triple Double









Ratio of W:F




The chart above makes it all clear. The ratio is too high in the original, too low in the Double Stuf, and just right in the Triple Double. Indeed, the Triple Double Oreo is the Little Bear’s porridge of the cookie world.

This reminds me of Reese’s Peanut Butter Cups. While I haven’t quantitatively analyzed the peanut butter to chocolate ratio, qualitatively I would say that the original had a little too much peanut butter, the Big Cup was disgusting with far too much peanut butter, but nirvana was captured with the peanut butter to chocolate ratio in Miniature Reese’s Peanut Butter Cups. (Insert smacking lips sound here.)

So if you read this blog and wonder why I’m so hyper sometimes, now you know. I consume an unholy amount of refined sugar.

1 There is some debate about the actual amount of filling contained in a Double Stuf Oreo cookie. Although a spokesperson for Nabisco claimed that the cookies indeed contain twice as much filling as a regular Oreo, a math class in upstate New York experimentally found that Double Stuf cookies contain only 1.86 times as much cream filling as a regular Oreo. As I generally trust unpaid high school students more than money-grubbing corporate types, I’m using 1.86.

2 The numbers for “filling” are relative to the amount of cream filling in a regular Oreo®.

December 22, 2013 at 9:30 pm 8 comments

SudoClue for a Cold Winter’s Night

SickThe holiday break is nigh, which means you need to be careful not to catch a cold.

For many people, the time preceding a holiday, vacation, or spring break is busy — finishing up a term paper, completing holiday shopping, or getting things off your desk so you can enjoy your trip to Tahiti. During that time, your immunity kicks into high gear. It helps to fend off germs while you’re pushing yourself to get stuff done. When your break finally comes, though, you relax, and your body thinks, “Oh, cool, the stress is over.” And BAM! No more immunity, and your body succumbs to infection. Sniffles, headache, and a cough ensue.

How can you prevent this?

Easy. Do puzzles.

That’s right. You can trick your body into thinking that you’re still stressed by doing crosswords, sudoku, nurikabe, battleship, nonogrids, or whatever you like. Your mind is working hard, so your body keeps your immunity up. Doing something you enjoy fends off disease. Win-win.

Well, MJ4MF is here to help. The following SudoClue puzzle will provide a half-hour of much-needed stress. The idea is rather simple. Use the clues to fill in the corresponding squares of the 6 × 6 grid, then fill in the remaining squares like a sudoku puzzle.

The puzzle below, as well as an easier version, are available in PDF format.

SudoClue Puzzle – Easy       SudoClue Puzzle – Hard


Pseudoku Puzzle

  1. Number of unique tetrominoes
  2. Product of all single-digit divisors of 143
  3. Number of English words that end with –dous
  4. Half of π2, approximately
  5. Number of tetrominoes that can be drawn without lifting your pencil from the paper
  6. 0!
  7. Number in the title of the greatest math joke book ever
  8. Integer between e and π
  9. Circumference divided by radius, to the nearest whole number
  10. Smallest number of colors sufficient to color all planar maps
  11. V
  12. Side length of a square whose area (in square units) is equal to its perimeter (in units)
  13. A perfect number
  14. A hat trick
  15. For integer values of n, the smallest prime divisor of n2 + n
  16. Number of total handshakes when four people shake hands with each other

Don’t feel like thinking too much on holiday break? Fine, here’s a hint. And if you’ve already fully entered holiday break mode, here’s the solution.

December 17, 2013 at 9:45 pm Leave a comment

Amazon Sales Rank, and What Math Geeks Do

Today, I asked my son’s if they would like to buy The Oatmeal’s Why Grizzly Bears Should Wear Underpants. They laughed uproariously at the title, and then Eli asked, “Is that the #1 book on Amazon?” In fact, it’s not. At the time of this writing, its ranking was #624. “That’s not #1,” Alex affirmed, then added, “but it’s a lot better than your book.”


“A lot better” is highly subjective. Sure enough, the #3,517 ranking of Math Jokes 4 Mathy Folks has an absolute difference of 2,893 compared to WGBSWU; or, if you’re into ratios, the rank of my book is five times as much as the rank of WGBSWU. But what does that really mean?

In practical terms, it means that the number of copies of WGBSWU that will sell on Amazon this week is approximately six times the number of copies of MJ4MF that will sell during the same period. If my calculations are correct, that is. No one is really sure how ranking translates to sales, but I estimate that approximately 250 copies of MJ4MF and 1,500 copies of WGBSWU will sell this week.

This is what math geeks do: We try to understand everything quantitatively.

I took weekly sales data for MJ4MF and compared that with the book’s average ranking for the week. I randomly chose 20 weeks in 2012-13 for this analysis, because while pulling weekly sales data is relatively easy — it’s provided at Amazon Author Central — determining weekly average ranking is more difficult, since data has to be pulled day by day. And it’s not as simple as just exporting the data to Excel or a CSV file… the data is provided in a graph, and if you want to manipulate that data in any way, you have to look at each point on the graph, determine its value, and then enter it manually. Ugh.

The graph below shows the relationship between average rank and weekly sales:

Sales vs. Rank

The regression equation S = 914.77 × R-0.977 gives a reasonably good fit (r = 0.89). What’s interesting is that this formula is less accurate in November and December than during the rest of year. There are two reasons for that. First, sales increase dramatically during the holiday shopping season. Second, such a formula is bound to be less accurate with larger numbers.

The average rank for December 9-15 was #3,592, and using the formula above, approximately 253 copies of MJ4MF should have sold. (I suspect that estimate is a little low. For the same week last year, the average rank was #4,573 and 277 copies were sold.)

Amazon posts sales data for each week on the following Friday. Sales data for last week won’t post until December 20. I’ll update this post on Friday and let you know how well I did.

[Update, 12/20/13: A record-breaking 335 copies of MJ4MF sold December 9-15. (Thank you!) But as predicted, the estimate was indeed low. As I gather more data, perhaps I will be able to create a better model.]

December 15, 2013 at 12:28 pm Leave a comment

Help Wanted at the Math Diner

The following is a Help Wanted ad that Alex made in school.

Math Diner Help Wanted

Were I to open a restaurant, I would look for similar qualities in my wait staff: sharp and curvaceous.

The slogan would be:

The Math Diner — where everyone gets a square meal!

And the menu would include the following items:

  • Prime Rib
  • Free-Range Chicken
  • Mathed Potatoes
  • Dim Sum
  • Chicken Pot Pi
  • Seven-Layer Dip
  • Three-Bean Salad
  • Root Beer
  • Petit Fours

December 11, 2013 at 8:02 am 2 comments

The Mathematics of Gift Wrapping

Has this ever happened to you?


You place a gift on the wrapping paper. You estimate how much you’ll need. You cut. You place the gift on the paper. You fold over both sides.


That’s when you realize your estimation skills are on par with those of a government contractor.

But, no worries! Math is here!

The hypotenuse of a right triangle is longer than either leg. Consequently, turning the wrapping paper at an angle will allow the paper to cover the gift.



My wife hates it, but whatever! What initially appeared to be a terrible estimate yielded a 15.8% savings in wrapping paper.

Based on my calculations, if all gifts were wrapped this way, the country would save $147 million each year on wrapping-paper related expenses. (Where’s that statistic when politicians discuss the economy?)

December 7, 2013 at 11:06 pm Leave a comment

Pigs in the Gutter

Finals are just around the corner, and another semester will soon be in the books. Here’s a poem to relieve the tension for all of you preparing for final exams — whether taking or administering them.

Late in the fall semester,
Dressed in suede and polyester,
I was thinking ‘bout a theorem I’d derived;
So drunk was I with mathy passion,
Into the gutter I went crashin’,
And a pig came up and lay down at my side.

Yes, I lay there on my rear end
With my stinky, pinky new friend
When a woman passing by did softly say,
“You can tell a mathy creep
By the company he’ll keep” —
And the pig got up and slowly walked away.


I don’t want to, but I gotta…

We lay side-by-side in the gutter for quite some time — swine and co-swine.

December 4, 2013 at 3:38 pm Leave a comment

About MJ4MF

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.

Past Posts

December 2013

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