## Posts tagged ‘coffee’

### Math Jokes for National Doughnut Day

Today is National Doughnut Day, and if you need your fix, *Time* reports that free doughnuts are available from Dunkin’ Donuts, Krispy Kreme, Tastykake or Winn Dixie.

At MJ4MF, we can’t let this day pass without telling the obvious joke…

A topologist is a mathematician who can’t tell a coffee cup from a doughnut.

And the modification…

How many topologists does it take to change a light bulb?

Just one. But what’ll you do with the doughnut?

To help you celebrate, here’s a doughnut-related math problem.

Several years ago, Dunkin’ Donuts ran a commercial bragging about how picky they were. The commercial stated:

We reject more than one million pounds of coffee beans a year.

Sure sounds impressive, doesn’t it? But how picky are they, really? Do a back-of-the-envelope estimate, and I think you’ll realize that they’re not all that picky after all.

### Brew Me a Cup!

International Coffee Day is celebrated on September 29, and in the United States the week leading up to it is known as National Coffee Week. This is good news for mathematics. If Alfréd Rényi (or perhaps Paul Erdös?) was correct, then we should defintely see an uptick in the number of theorems produced this week…

A mathematician is a device for turning coffee into theorems.

Should you need caffeine-induced inspiration for the work you’re doing this week, there are plenty of places giving out free cups of joe.

The following corollary is attributed to Paul Turán:

Weak coffee is suitable only for lemmas.

Peter Cameron argues that all math departments should have an adequate supply of the highest possible grade of fuel.

…the effects of coffee (better theorems, more collaboration, more collegiality) are not immediately obvious to administrators, and are not easily quantified (unlike the costs). But they are worth fighting for!

A. J. Tolland is fond of saying, “What we really need is a machine for turning some of those theorems back into coffee.” Kevin Buzzard tells the following story, which seems that this is possible:

Kenneth Ribet once said that he was sent a textbook by a publisher, with the suggestion that he use it in his undergraduate course. He decided not to, and sold it to a second-hand bookstore for a few dollars. On the walk back, he bought some coffee with the money, and then realised to his amusement that he’d done precisely what Tolland had suggested.

And one non-math joke for the week:

Men (or women) are like coffee — the best ones are hot, rich, and keep you up all night!

Cheers!

### What’s the Difference?

Today is 8/20/12, which makes it a *difference day*, because the difference between the date and the month is equal to the year: 20 – 8 = 12. In general, a day in the form *mm*/*dd*/*yy* is a difference day if *dd* – *mm* = *yy*.

Dates of this type are relatively rare. There will be exactly 12 per year through 2019, but from 2031 through 2099, there won’t be any. So here’s a question:

How many difference days will there be during the 21st century?

The answer is below.

Speaking of differences, here are some math jokes about differences.

**What’s the difference between a narcoleptic and a math professor?**

The narcoleptic is a slumber nut.

**What’s the difference between a math Ph.D. and a large pizza?**

A large pizza can feed a family of four.

**What’s the difference between a lemma and a proposition?
**You’ll never receive a lemma at a bar.

**What’s the difference between a mathematician and a chocolate muffin?
**One is a mathematician, and the other is a chocolate muffin.

Though I believe mathematicians are useful, I would much prefer a machine for turning theorems into coffee.

(Admittedly, that last one is in the wrong format. But it seems weird to ask, “What’s the difference between a mathematician and a machine for turning theorems into coffee?” The answer would be, “Nothing.”)

There will be 281 difference days during the 21st century. There are 12 per year for 2000–19, but then the number per year starts to decrease. You might expect there to be 11 difference days in 2020, 10 difference days in 2021, and so on, with the number decreasing by 1 each year. But February, April, June, September and November cause problems because they have fewer than 31 days. So the total number of difference days during the 21st century is:

20(12) + 10 + 10 + 8 + 8 + 7 + 5 + 5 + 3 + 3 + 1 + 1 = 281

### I Like My Women Like I Like My Math

My father had a predilection for embarassing my mother. For instance, when a waitress would ask how he’d like his coffee, he’d say:

I like my coffee like I like my women — hot, sweet, and light.

My father was the original bigot chauvinist. Had I been taking notes, I could have written *Sh*t My Dad Says* twenty years ago. Here are a few other similes that I think my father would have appreciated:

I like my women like I like my mathematics — pure and beautiful, not complex and irrational.

I like my women like I like my math tests — full of problems, and easy to cheat on.

I like my women like I like my math problems — simple and easy.

I like my women like I like my calculus textbooks — full of curves.

I like my women like I like my research papers — interesting, intelligent, and covered in ink.

I like my women like I like my data — average, and within my range.

I like my women like I like my equations — well-balanced.

I like my women like I like the tenth positive odd number — prime, and over 18.

I like my women like I like my ellipses whose major and minor axes are almost equal — just a little eccentric.

I like my women like I like the roots of

x^{2}+ 2x+ 1 = 0 — degenerate, and easy to find.I like my women like I like my calculator-dependent students — with no interest in multiplying.

### Reap What You Sow

Yesterday, our home owner association paved and painted the parking lot behind our townhouse. My twin three-year-old sons, Alex and Eli, were fascinated by the large, white numbers that now adorn each parking spot. They counted all of the numbers out loud, which ranged from 16 to 37. “Where is 1?” Alex asked.

The lot behind our house is Parking Lot B; spaces 1‑15 are in Parking Lot A. I probably should have explained this to him, but instead I just said, “There’s no number 1 in our parking lot. This lot begins with number 16. Isn’t that an odd number with which to begin a parking lot?”

He responded, “No, daddy. Sixteen is an **even** number, actually.”

I suppose that’s what I deserve for teaching my kids about parity before their fourth birthday.

This incident reminded me of the following joke, which appears in a slightly different form in *Math Jokes 4 Mathy Folks*:

A teacher asks her class, “How can you divide 25 sugar cubes among 3 cups of coffee so there is an odd number of cubes in each cup?”

Bekkah responds, “Put one in the first cup, and put 12 in each of the other cups.”

“But 12 isn’t an odd number,” the teacher replies.

“Sure it is,” Bekkah replies. “Twelve is a very odd number of sugar cubes to put in a cup of coffee!”

This joke is typically told so that the teacher asks students to divide 14 sugar cubes into 3 cups of coffee, and the student says to divide them as 1, 1, and 12. I never liked that version, though, because the problem as posed by the teacher is unsolvable — that is, there is no way to divide 14 sugar cubes such that there is an odd number in each cup. Yes, I know it’s only a joke… but I like to think that a teacher would only ask a question that had a solution.