Periodically Crude

Old farts will know the answer to this old trivia question:

What two letters do not appear on a phone?

And if your phone still looked like this…
Rotary Phone
then it would be a reasonable question.

But phones don’t look like that anymore. They look like this…
phone-powerof2
in which case, it’s a really dumb question. (The Q is now attached to 7, and Z hangs out with 9.)

On the other hand, the periodic table looks the same today as when Mendeleev published it in 1869, so the following trivia question may be a bit better:

What two letters never appear in a chemical abbreviation on the periodic table? (I mean anywhere, bitches.)

Shouldn’t be that hard, if you’re willing to take the time to look.

Jessica Lee made headlines back in May when she placed the following quote in her yearbook:

Fluorine uranium carbon potassium bismuth technetium helium sulfur germanium thulium oxygen neon yttrium.

Seems innocuous enough, till it’s translated with the periodic table:

Jessica Lee Quote

(A line from a Notorious B.I.G. song, for the old farts reading this.)

Are you made of nickel, cerium, arsenic and sulfur? Because you have a…

Nice AssOr maybe you’re made of copper and tellurium? Because you’re…

CuteIf you got nothing better to do today, maybe you could take a ride on a ferrous wheel…

Ferrous Wheel

September 22, 2014 at 7:56 am Leave a comment

Ahoy, Matey! Math Jokes Ho!

A ditloid is a puzzle in which a fact must be discerned from the numbers and abbreviated letters in the clue. For example, 7 D in a W is a ditloid for “7 Days in a Week,” and 20 V on a D is a ditloid for “20 Vertices on a Dodecahedron.”

Here’s a ditloid in honor of International Talk Like a Pirate Day:

15 M on a D M C

If you have trouble, here’s a hint.

Also for International Talk Like a Pirate Day, some mathy pirate jokes.

Teacher: What’s the circumference of a circle?
Pirate: 2π Arrr!

How much did the pirate pay to have his ears pierced?
A buccaneer!

What has eight legs and eight eyes?
Eight pirates!

What grade did the pirate get in math class?
High C’s!

When Apple finally enters the pirate arena… the iPatch.

iPatch

September 19, 2014 at 1:56 am 2 comments

Book Review: 365 Things To Make You Go Hmmm…

365 ThingsBefore reading 365 Things That Make You Go Hmmm…, I hadn’t realized that I’d been on Earth for 1.3 billion seconds, and I never thought about what someone would feel like after spending a day in my mind. That’s the beauty of this incredible book — it asks you to think about things that you’ve probably never thought about before. The questions are great for starting classroom discussions, but they also work well for sparking a conversation between a parent and child, or as an icebreaker at your next social event.

The book contains introspective questions (“What makes you irreplaceable?”), but it also contains math and logic puzzles like the following:

Before this piece of paper was folded over once, it was a capital letter. It wasn’t the letter L — that would be too easy. Which letter was it?

Folded Letter

I’m also a big fan of puzzle #110, which starts:

An antigram is word [or phrase] that when you rearrange the letters you can make a new word or phrase that means something very different — in fact, almost the opposite! For example: earliestrise late.

It then provides a list of antigrams and asks for the opposite word or phrase. One of the antigrams is:

within earshot

Flummoxed, I looked at the answer in the back of the book, which read:

I won’t hear

I realized immediately that something was wrong. The given answer did not contain enough letters. And then I gasped, because I realized which letters had been omitted:

Within Earshot

Wow! I emailed Paul Wrangles (the author) immediately and asked if the answer was given as “I won’t hear” so as to avoid writing “I won’t hear shit,” or if this was simply a typo. He assured me that it was only a typo, and the correct answer is supposed to be:

I won’t hear THIS

Whew!

With that mystery solved, I viewed the other 360 things and thoroughly enjoyed them. My sons and I have been working our way through them, though they’re so addictive, we rarely stop at answering just one a day. We’re hoping for a second volume — we need more questions to last an entire year!

365 Things That Make You Go Hmmm… is an amazing resource. Chock full of questions from ordinary to extraordinary, it made my head hurt — but in a good way!

I highly recommend this book for any teacher, parent, or curious individual.

September 15, 2014 at 6:54 am Leave a comment

Exponentially Smarter, Literally

To show my sons what Siri can do, I asked her (it?) the following question:

What is 6 + 4?

Siri told me, “The answer is 10.” But she also provided a bunch of other information pulled from Wolfram Alpha, including the following data:

Wolfram Computation Times

This data appears to be taken from dissertation research by B. A. Fierman which was furthered by psychologist Mark H. Ashcraft. What it shows is that we get exponentially smarter — or at least faster at calculating — as we get older.

According to Excel, this data can be modeled exponentially by y = 8.36 · e–0.129x, though this model has obvious limitations. For example, it implies that a one-year-old would be able compute this sum in 7.35 seconds, yet I know no one-year-old who understands addition. Further, it claims that it would take me 0.03 seconds to compute the sum, but I would argue first that I don’t compute the sum, I merely recall it; and second, my reaction time when asked for the sum would be greater than 0.03 seconds.

Playing around with the generic function y = abx + c using the world’s best graphing calculator from Desmos, I found a model that may approximate the data a little better:

y = 57 · 0.65x + 0.9

With this model, it would take a one-year-old 37.95 seconds to compute sum. That’s still not reasonable for any one-year-old that I know, but at least the model says it would take me 0.9 seconds to recall the fact, a far more reasonable estimate than the 0.03 seconds given by the Excel model above.

Interestingly, How To Geek claims that Siri uses Wolfram Alpha for 25% of its searches. Yet if you ask Siri, “What is the meaning of life?” it will respond,

I can’t answer that right now, but give me some very long time to write a play in which nothing happens.

or

Try and be nice to people. Avoid eating fat. Read a good book every now and then, get some walking in, and try to live together in peace and harmony with people of all creeds and nations.

On the other hand, if you ask Wolfram Alpha, “What is the meaning of life?” it will respond,

42.

Proper.

All this talk of exponentials reminds me of a joke.

Q: How do you know that your dentist studied algebra?

A: She tells you that candy will lead to exponential decay.

Perhaps the most famous joke about exponentials is not one of which I’m terribly fond. I share it here only to honor my mission of providing math jokes to the world, not because I think any of you will enjoy it.

Several functions are sitting in a bar, bragging about how fast they go to zero at infinity. Suddenly, one hollers, “Look out! Derivation is coming!” All of the functions immediately cower under the table, but the exponential function sits calmly on the chair.

The derivation comes in, sees the exponential function, and says, “Don’t you fear me?”

“No, I’m ex,” says the exponential confidently.

“That’s all well and good,” replies the derivation, “but who says I differentiate with respect to x?”

September 11, 2014 at 9:11 am 2 comments

Math Jokes from Reader’s Digest

All of the following jokes were borrowed from Reader’s Digest, which I’m sure they borrowed from elsewhere.

Did you hear about the mathematician who’s afraid of negative numbers?
He’ll stop at nothing to avoid them.

How easy is it to count in binary?
It’s as easy as 01 10 11.

A Roman walks into the bar, holds up two fingers, and says, “Five beers, please.”

How many bananas can you eat if your stomach is empty?
Just one. Then it’s not empty anymore.

What do you call a number that sleepwalks?
A roamin’ numeral.
(And a nun who sleepwalks?
A roamin’ Catholic.)

Knock! Knock!
Who’s there?
Convex.
Convex who?
Convex go to prison!

September 8, 2014 at 5:45 pm 1 comment

Ring Me Up!

Cash RegisterWhen my college roommate contracted crabs, he went to CVS to buy some lice cream. As you can imagine, he didn’t want to announce to the world what he was buying or why, so he put the box on the counter with a notepad, a bottle of aspirin, a pack of cigarettes, a bag of M&M’s, and a tube of toothpaste — hoping the cream would blend in. The attractive co-ed clerk at the register rang him up without a second look.

As he walked out of the drug store thinking he had gotten away with it, he opened the cigarettes, put one to his lips, and realized he had nothing with which to light it. He returned to the checkout and asked the clerk for a pack of matches.

“Why?” she asked. “If the cream doesn’t work, you gonna burn ‘em off?”

Ouch.

My luck with clerks wasn’t much better. At a grocery store, I placed a bar of soap, a container of milk, two boxes of cereal, and a frozen dinner on the check-out counter. The girl at the cash register asked, “Are you single?”

I looked at my items-to-be-purchased. “Pretty obvious, huh?”

“Sure is,” she replied. “You’re a very unattractive man.”

I did, however, have an exceptional experience at a convenience store. This is what happened.

I walked into a 7-11 and took four items to the cash register. The clerk informed me that the register was broken, but she said she could figure the total using her calculator. The clerk then proceeded to multiply the prices together and declared that the total was $7.11. Although I knew the prices should have been added, not multiplied, I said nothing — as it turns out, the result would have been $7.11 whether the four prices were added or multiplied.

There was no sales tax. What was the cost of each item?

As you might have guessed, that story is completely false. (The one about me being called ‘unattractive’ is a slight exaggeration. The one about my roommate, sadly, is 100% true.) The truth is that I learned this problem from other instructors when teaching at a gifted summer camp.

It may not be true. It is, however, one helluva great problem.

But it has always bothered me that the problem is so difficult. I’ve always wanted a simpler version, so that every student could have an entry point. Today, I spent some time creating a few.

Use the same set-up for each problem below… walk into a store… take some items to check-out counter… multiply instead of add… same total either way. The only difference is the number of items purchased and the total cost.

I’ve tried to rank the problems by level of difficulty. Below, I’ve given some additional explanation — but not the answers… you’ll have to figure them out on your own.

  • (trivial) Two items, $4.00.
  • (easy) Two items, $4.50.
  • (fun) Two items, $102.01.
  • (systematic) Two items, $8.41.
  • (perfect) Three items, $6.00.
  • (tough) Three items, $6.42.
  • (rough) Three items, $5.61.
  • (insane) Four items, $6.44.
  • (the one that started it all) Four items, $7.11.

Editor’s Notes

trivial — C’mon, now… even my seven-year-old sons figured this one out!

easy, fun, systematic — All of these are systems of two equations in two variables. Should be simple enough for anyone who’s studied basic algebra. All others can use guess-and-check.

perfect — Almost as easy as trivial, and the name is a hint.

tough — But not too tough. Finding one of the prices should be fairly easy. Once you have that, what’s left reduces to a system of equations in two variables.

rough — Much tougher than tough. None of the prices are easy to find in this one.

insane — Gridiculously hard, so how ’bout a hint? Okay. Each item has a unique price under $2.00. If you use brute force and try every possibility, that’s only about 1.5 billion combinations. Shouldn’t take too long to get through all of them…

the one that started it all — As tough as insane, and not for the faint of heart. But no hint this time. Good luck!

 

September 5, 2014 at 7:11 am Leave a comment

A Gridiculously Clever Blog Post

Do you know what the following graph represents?

Sine on the Dotted Line

Sine on the dotted line.

If you tell that joke to the right audience, you’ll likely hear a triggle. (If you tell it to the wrong audience, you’ll likely hear the sound of tomatoes whizzing past your head.)

Triggle is a portmanteau, a combination of two or more words and their definitions.

trigonometry + giggle = triggle

In a similar vein, when the expression

13 + 5 · 0 – 4

is simplified to

13 – 4,

you might say that it has suffered from zerosion — the removal of a term because of multiplication by zero.

The following portmanteaux may be useful for your next math discussion.

bi·sect·u·al
adjective
attracted to both halves of an angle

grid·ic·u·lous1
adjective
inviting derision on the coordinate plane

cha·rad·i·us
noun
a segment from the center to the circumference based on false pretenses

bi·zarc
noun
an unusual curve

graph·ish
adjective
diagrammatically disreputable

sub·line
adjective
inspiring awe in only one dimension

trig·a·ma·role
noun
a complicated and annoying trigonometric process, such as verifying that
cot x + tan x = sec x · csc x


1 It came to my attention after the publication of this post that Gridiculous is (a) a trivia game developed for Windows 8 and (b) an HTML5 responsive grid boilerplate (though the link to the site seems not to be working).

September 2, 2014 at 4:07 pm Leave a comment

Older Posts


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

September 2014
M T W T F S S
« Aug    
1234567
891011121314
15161718192021
22232425262728
2930  

Enter your email address to subscribe to the MJ4MF blog and receive new posts via email.

Join 112 other followers

Visitor Locations

free counters

Follow

Get every new post delivered to your Inbox.

Join 112 other followers