## Posts tagged ‘math’

### Ch-Ch-Ch-Changes — in Job and Location

**A few days back**, I mentioned that I had a new job and had moved across the country, and I said I’d write more about that later. Well, it’s later.

After six wonderful years of developing a highly-rated, award-winning, interactive math textbook at Discovery Education, I’ve taken a new position at the **Math Learning Center**, a non-profit organization in Portland, Oregon. The Math Learning Center (MLC) is the publisher of *Bridges*, an award-winning elementary math curriculum.

The reason for the change? Well, actually, there are several…

- MLC is not-for-profit, so any money raised from curriculum sales is used to improve the materials and professional development offerings.
- The mission of the Math Learning Center is “to inspire and enable individuals to discover and develop their mathematical confidence and ability.” It’s pretty easy to get behind a goal like that.

- Last but not least, the MLC staff might be the friendliest group of individuals I’ve ever met. To boot, they’re bright, hard-working, and dedicated to the organization’s mission.

With all that, the decision to join MLC was a rather easy one. If you can’t tell, I’m pretty excited about the change. I’ll be the new Chief Learning Officer, affectionately known as the **CLO**.

Time out for a puzzle.

Can you fill in the blanks to form a 16-letter math term that contains the letters CLO in order? Hint: think about transformational geometry or turning off the faucet.

_ _ _ _ _ _ _ C L O _ _ _ _ _ _

Relocating from Virginia to Oregon is a big deal. It’s nearly 2,800 miles — or 14 states, or 42 hours in a car — from our old house to our new one. Consequently, we hired a moving company to help with packing and shipping. When Lily from the moving company arrived, she asked if we had any “high-value items” to be transported, such as expensive jewelry or fur coats. (But not a real fur coat. That’s cruel.) I said that I didn’t think so, but then I asked what they consider a high-value item. Lily’s answer used a completely acceptable but surprising unit rate:

**anything over $100 per pound**

With that metric, it was suddenly obvious that we had several high-value items in our home. The first was a pair of diamond earrings that I had given my wife recently for our 15th anniversary. Since 5 carats = 1 gram, these small hunks of rock have a retail value of nearly $4,000,000 per pound, significantly above the moving company’s threshold.

The other high-value items were, well, *us*. The “value of statistical life,” or VSL, is a measure of the value of a human life. Its exact amount depends upon which federal agency you reference. The Environmental Protection Agency (EPA), for instance, pegs the VSL at $10 million. That means that I’m worth approximately $50,000 per pound, my petite wife is worth nearly $80,000 per pound, and our twin sons are worth well over $100,000 per pound each.

Granted, our value density isn’t as high as diamond, but we’re still pretty darn valuable.

A cannibal goes into a butcher shop, and he notices that the market specializes in brains. He sees that the butcher is selling engineer’s brain for $1.50 per pound, mathematician’s brain for $2.25 per pound, and politician’s brain for $375.00 a pound. Flabbergasted, he asks the owner why the huge difference in price. The butcher replies, “Do you have any idea how many politicians it takes to get a pound of brains?”

In the end, neither the diamond earrings nor any member of our family were loaded onto the moving truck. A week later, we’re adapting nicely to Portland culture, and I start my job at Math Learning Center in just a few days. Wish me luck!

### Silent Letter Night

Several weeks ago, Will Shortz presented an NPR Sunday Puzzle in which he stated a word and a letter, and the resulting collection would be rearranged to form a new word in which *the added letter is silent*. For instance, if Will gave RODS + W, the correct answer would be SWORD, in which the W is silent. (Note that the collection of letters is also an anagram of WORDS, but the W isn’t silent.)

At a time of year known for silent nights, it seems like a puzzle involving silent letters is completely appropriate. I’ve borrowed Shortz’s idea and extended it a bit; some of the clues in the list below have more than one silent letter added. Many items in the list are related to today’s holiday; and, because this is a math blog, the others are related to mathematics. In full disclosure, two of the answers are proper nouns.

Enjoy, and happy holidays!

- TO + W =
- TON + K =
- TOGS + H =
- GEE + D =
- TIN + G + H =
- SIN + G =
- SIN + E =
- CORD + H =
- HOLE + W =
- HEART + W =
- TINNY + E =
- COINS + E =
- NOELS + M =
- PILES + E + L =
- FRAME + T =
- REDACT + E + S + S =
- RACISMS + H + T =

### What’s in Your Pocket?

I recently received an email from adoring fan Alden Bradford:

Teacher: “Would you like a pocket calculator?”

Student: “No, thanks. I already know how many pockets I have.”

Thanks, Alden!

Of course, that reminded me of this gem from Spiked Math:

And one final pocket joke:

The department chair said to the math teachers, “I have good news, and I have bad news. The good news is, we have enough money for a new microwave in the staff lounge.” The teachers cheered! Then one of them asked, “What’s the bad news?” The chair said, “It’s still in your pockets.”

Ouch.

### Math Words for National Dictionary Day

Want to start today the right way? Say, “Good morning!” to Alexa today, and she’ll respond:

Good morning! It’s National Dictionary Day. Ever wonder what the shortest word is? Technically, it’s a toss-up between the single letter words

andI, but sinceais always capitalized, I’d sayIis just a little shorter.a

Is there anything more powerful than a language arts joke to get the day off to a good start?

I have no words to describe today. I do, however, have a ton of obscene gestures.

So, what’s the shortest **math** word? Technically, *e* and *i*, but if you don’t like constants, then you’ll have to settle for the three-letter words *set* and *box*.

And what’s the longest math word — at least based on the list at Math Words? It has 17 letters, and you’ll get a big hint if you check the time.

What two math words, both having the same number of letters, are equally appropriate to describe a triangle whose sides are congruent?

And what’s the funniest math word? Personally, I think it’s *syzygy*, but according to Tomas Engelthaler, it’s *logic*. In Humor Norms for 4,997 English Words, Engelthaler and Hills (2017) describe a method for determining which words are funniest. I emailed Engelthaler to ask which math word is funniest, and he responded as if it were a completely reasonable question. Without hesitation, he shared a list of math words and their humor rankings, and these five were at the top of the list:

- logic
- math
- theory
- science
- graph

The overall funniest English word, according to Engelthaler’s research? *Booty*. Go figure.

While you may not think that any of those words, mathy or otherwise, are laugh-out-loud funny, this isn’t debatable; it’s based on science.

If you take issue with this research, you’ll need to discuss it with Engelthaler and his colleagues. Please write to him directly to say that you’re bumfuzzled, that his research is malarkey, or that you think he’s a nincompoop.

### Required Summer Reading: *The Grasshopper King*

If you’ve read *How Not to Be Wrong: The Power of Mathematical Thinking*, then you know that Jordan Ellenberg is extremely intelligent, well educated, and incredibly talented. In addition, he may be the best voice for mathematics in America today. (You may have come to the same conclusion by reading his “Do The Math” column in *Slate* or from any one of the articles he’s written for *The New York Times* or *The Wall Street Journal*.) But if you haven’t read *The Grasshopper King*, a nonfiction novel that Ellenberg wrote in 2003, then you are absolutely missing out on his gifts as a pure writer. It’s the tale of Stanley Higgs, an internationally acclaimed professor of Gravinics at Chandler State University; Samuel Grapearbor, a graduate student at CSU; and the silent relationship that forms when Grapearbor is assigned to watch Higgs after he decides — for no obvious reason — to stop talking.

Coffee House Press claims that the novel is about “treachery, death, academia, marriage, mythology, history, and truly horrible poetry.” I mean, what’s not to love?

I bought *The Grasshopper King* because of how much I enjoyed *How Not to Be Wrong*, but I had no intention of enjoying it nearly as much as I did. From the first page, though, I was enthralled with Ellenberg’s style. To amalgamate several of the Amazon reviews, “this is an unusual book,” but it is beautiful because of “the finely tuned precision of the writing itself.”

This is not a math book, but occasionally Ellenberg turns a phrase that reminds you he’s a mathematician. When Grapearbor’s girlfriend claims that New York is ninety-five percent liars and snobs, he replies, “In Chandler City it’s ninety-nine. Point nine repeating.” Other times, he’ll include mathematical terms that are, in fact, completely appropriate and economical, but not altogether necessary:

a grasshopper, stirred by some unguessable impulse, heaved itself out of the drench mess, rose and fell in a perfect, inevitable

parabolawhoseinterceptwas the exposed stripe of Charlie’s backthe pressure of the water made

concentric circlesbehind my clenched-shut eyelidsthe agricultural buildings were at

discreet distancesfrom one another

And, yes, I know that last one isn’t a math phrase… but I can’t help but read it as *discrete distances*.

If you like Pynchon or Wolfe or anything off the beaten path, then you’ll like this book. The characters are quirky and memorable, and the writing is unforgettable. I recommend spending a few hours with it during what you have left of this summer.

### There Are 2 Things that Happened Yesterday…

Yesterday was a banner day.

Last night, I was finally able to carve out some time to binge-watch Season 2 of *Trial & Error*, and I was rewarded with a classic math joke in Episode 1. When lead investigator Dwayne Reed arrives at the house of accused murderer Lavinia Peck-Foster, he says:

There are two things that Reeds don’t trust: doctors, Pecks, and math.

I love it!

Upon realizing that I might be able to get my sitcom-writing career off the ground by reformulating stale math jokes, I promptly submitted my resume to NBC.

But, wait… there’s more!

Earlier in the day, I received NCTM‘s email newsletter *Summing Up*, which contained an unexpected surprise. In the section titled “NCTM Store,” there was a blurb about my most recent book, *More Jokes 4 Mathy Folks*, under the headline **Just Published!**

I had no idea that NCTM decided to sell my book, let alone that they were going to publicize it. My ignorance not withstanding, I couldn’t be more delighted!

If you’re looking for some great, light summer reading — something that can be enjoyed poolside while sipping a mojito — then pick up a copy of ** More Jokes 4 Mathy Folks** from NCTM today! Not only will your purchase support a great organization (and my sons’ college fund), you’ll also receive a 20% discount for being an NCTM member.

Following the lead of Dwayne Reed, here are jokes that begin, “There are *n* kinds…,” all of which appear in *More Jokes 4 Mathy Folks*:

- There are only 2 kinds of math books: those you cannot read beyond the first sentence, and those you cannot read beyond the first page. (C. N. Yang, Nobel Prize in Physics, 1957)
- There are 2 kinds of people in the world: those who don’t do math, and those who take care of them.
- There are 3 kinds of people in the world: positive, negative, and relative.
- There are 2 kinds of people in the world: those who are wise, and those who are otherwise.
- There are 2 kinds of statistics: the kind you look up, and the kind you make up.
- There are 2 kinds of experienced actuaries: those who say they have made significant forecasting errors, and liars.
- There are 10 kinds of people in the world: those who understand binary, and those who don’t.
- There are 10 kinds of people in the world: those who understand binary, and 9 others.
- There are 10 kinds of people in the world: those who understand ternary; those who don’t understand ternary; and, those who mistake it for binary.
- There are 11 kinds of people: those who understand binary, and those who don’t.
- There are 8 – 3 × 2 kinds of people in the world: those who correctly apply the order of operations, and those who don’t think that 6 ÷ 2 × (1 + 2) = 9.
- There are 2 kinds of people in the world: logicians and ~logicians.
- There are 2 kinds of people in the world: those who can extrapolate from incomplete data…

### Stick Figure Math

I’ll never forget the first time I saw the pattern

1, 2, 4, 8, 16, __

and was dumbfounded to learn that the missing value was **31**, *not 32*, because the pattern was *not* meant to represent the powers of 2, but rather, the number of pieces into which a circle is divided if *n* points on its circumference are joined by chords. Known as Moser’s circle problem, it represents the inherent danger in making assumptions from a limited set of data.

Last night, my sons told me about the following problem, which they encountered on a recent math competition:

*What number should replace the question mark?*

Well, what say you? What number do you think should appear in the middle stick figure’s head?

Hold on, let me give you a hint. This problem appeared on a multiple-choice test, and these were the answer choices:

- 3
- 6
- 9
- 12

Now that you know one of those four numbers is *supposed* to be correct, does that change your answer? If you thought about it in the same way that the test designers intended it, then seeing the choices probably didn’t change your answer. But if you didn’t think about it that way and you put a little more effort into it, and you came up with something a bit more complicated — like I did — well, then, the answer choices may have thrown you for a loop, too, and made you slap your head and say, “WTF?”

For me, it was Moser’s circle problem all over again.

So, here’s where I need your help: **I’d like to identify various patterns that could make any of those answers seem reasonable.**

In addition, I’d also love to find a few other patterns that could make some answers other than the four given choices seem reasonable.

For instance, if the numbers in the limbs are *a*, *b*, *c*, and *d*, like this…

then the formula 8*a* – 4*d* gives 8 for the first and third figures’ heads and yields 8 × 6 – 4 × 9 = **12** as the answer, which happens to be one of the four answer choices.

Oh, wait… you’d don’t like that I didn’t use all four variables? Okay, that’s fair. So how about this instead: ‑3*a* + *b* + *c* – 2*d*, which also gives ‑3 × 6 + 7 + 5 + 2 × 9 = **12**.

Willing to help? **Post your pattern(s) in the comments.**

[**UPDATE (3/9/18):** I sent a note to the contest organizers about this problem, and I got the following response this afternoon: “Thanks for your overall evaluation comments on [our] problems, and specifically for your input on the Stick Figure Problem. After careful consideration, we decided to give credit to every student for this question. Therefore, scores will be adjusted automatically.”]