# Scenes from the “Real World” Where Math is Useful

…when you run into a college classmate who dropped out after suffering from health issues. You always meant to write a nice, sympathetic letter of support, but it never crested to the top of your to-do list, and now your long silence seems callous. The classmate sees you, looks away, then marches right up to you and asks, point-blank, the question you’ve dreaded for years:

“Why,” your classmate spits, “does raising both sides of an algebraic equation to an even power potentially introduce extraneous solutions?”

…you’ve already skimmed every worthwhile article in the newspaper. You completed the crossword, the Sudoku, even the word jumble. Grudgingly, you turn to the paper’s last remaining puzzle: the Partial Differential Equation of the Day.

A difficult man, largely neglected by his own children, he has come to embrace you as one of his few points of contact beyond the nursing home. Now, in his waning hours, he mistakes you for his estranged son, Bradley, and delivers a tearful apology. “I was a terrible father,” he says. “Forgive me, Brad.”

“I do,” you say.

“If you truly forgive me,” he wheezes, “then prove it. Tell me the quadratic formula, one last time.”

…your desktop breaks down. It won’t even boot up. A new computer (lasting an expected five years) will be \$800, or alternatively, you can diagnose the problem for \$70, and repairs (which would extend the computer’s lifespan an expected three years) could cost anywhere from \$50 to \$600, uniformly distributed.

Now, it may feel impractical as a replacement for a desktop, but look how pretty that tablet over there is. Look how shiny. Don’t you want a pretty, shiny tablet instead? Don’t you? Don’t you?

…by the frat-boy culture at your office, you find yourself in left field, dreading any ball hit your way. Suddenly, a pop-up: it should probably be yours, but instead, the shortstop and centerfielder converge on it, and collide—hard. The shortstop is out cold, blood oozing from a temple.

“Quick!” the centerfielder shouts. “Is anyone a doctor, nurse, or topologist?”

Silence follows.

“C’mon!” he screams. “We need someone to treat this wound, diagnose it, or prove its invariance under diffeomorphism!”

…and you’re craving potato chips. Still, you want to minimize the caloric damage, so you’re standing in the 24-hour liquor store, comparing brands. Lay’s nutrition label claims it has 200 calories per serving and 6 servings per bag, while the generic brand has 600isin(11π/6) calories per serving and 5i servings per bag.

“Looks like these chips have some complex carbohydrates!” you chortle. The guy behind the register smiles appreciatively.

…transcending corporeal existence. A four-dimensional hypercube and a six-dimensional analog of a torus are gossiping about a good friend of yours, an equiangular polygon undergoing a dilation. “Heh, I’d like to project into that plane!” the hypercube says, and they both laugh with cruel mirth.

Do you say something, or just keep walking?

There’s a math section on the GRE.

## 40 thoughts on “Scenes from the “Real World” Where Math is Useful”

1. Or you might want to do plumbing, electrical work, HVAC work, locksmithing, carpentry, machining, engine repair, or pretty much anything else that requires dealing with the physical world and making things work. Or you might want to handle money, or schedule time, or move things from one place to another. Or try to anticipate the behavior of, well, pretty much anything.

People who crow about how they never need to use math are, by and large, people who don’t actually do anything.There are huge numbers of people who receive a regular salary for not accomplishing anything.

1. Jimmy says:

You mean, like the Chicago Bears?

2. Yeah, you’re certainly right that math gets used all over the place (although most people, even those with real jobs, don’t use much past 8th grade math. Quadratics and logarithms just don’t come up in most workplaces).

My point was not than math is never useful, but that selling it to students based on ‘real-world’ value is a dangerous way to pitch it. Frame the conversation around practical utility, and students will measure every new topic against that yardstick. Many topics will then come up short, even if they really ARE useful for building understanding and analytic skills, just not for any immediate and obvious task.

Mostly, I think a teacher who feels obligated to give daily and satisfactory answers to ‘When am I ever going to need this?’ is likely to feel quite trapped, because even if you CAN justify school math on those grounds, it rarely seems to be the BEST justification.

1. Fair enough. Personally, I feel that a student who requires a teacher to justify the utility of a lesson prior to applying him- or herself to it has missed the entire purpose of education.

1. Agreed! It’s amazing(ly sad) that so many students feel education is an injustice inflicted upon them, rather than a service provided for their benefit.

2. Nice art and math combined. I wonder if Kepler would have enjoyed this! I think he would have liked this when explaining his laws of planetary motion. Do you agree?

1. I’m not arguing math has no uses, of course – the hyper-abstract work of logicians like Russell and Godel, for example, led directly to the modern computer.

Just pointing out (as Dan Meyer and others have also articulated, better than I) that the notion of “real world” we talk about in math classes doesn’t precisely correspond with the traditional meaning of the phrase.

3. “Looks like these chips have some complex carbohydrates!”

I see what you did there. 😀

4. If you pick your grad school carefully, you might not have to write the GRE. (I miscalculated with one school — they required the GRE but only AFTER acceptance.)

5. I started panicking at number 1, which is pretty much what happened at technical college…

6. Got me laughing, not totally because I know the ACTUAL logic, but because of how deep the terms were and it’s just funny.

7. Brilliant.

8. Math is my life’s biggest stress factor at the moment. I do so well in all of my other college classes, but for the love of me, I can not comprehend math!! Basically, I’m failing…and I need to fix that grade ASAP!

Funny post! Congratulations on being freshly pressed!

9. Lolol! This was soo good. No. 3 totally cracked me up! “Tell me the quadratic formula one last time.” Brilliant. Who said math isn’t funny! 😀

10. That’s a really cool post!!!
Awesome!

11. “…low-dimensional topologist…” I am equally thrilled my spellchecker could only recognize apologist, histologist, toxicologist, philologist BUT not “topologist” #topologistwhatsthat ? lol!

12. Reblogged this on malibehiribae and commented:
“…low-dimensional topologist…”. I am equally thrilled my spellchecker could only recognize apologist, histologist, toxicologist, philologist BUT not “topologist”. #topologistwhatsthat. lol!

13. charlyne says:

coucou 🙂

14. Oh, GOD! The GRE! (Did you know, some MFA programs do not require the GRE?!! I’m hoping to get away with NOT taking it. Tee hee.)

15. maybe i will need math… 😛 To be honest, sometimes I would just sit there in class thinking: “When will I ever need this?” Today, you have proved me wrong! 🙂 I’m glad I found your blog, it’s a great find, and I know I will enjoy reading all the posts! Thanks for posting! 😀

16. Reblogged this on thesearchforthefool and commented:
“To prove it… Tell me the quadratic formula one last time”

17. haha…this made me laugh. thanks for that. sadly, I don’t know if i’ll be following your blog…but this was a good read.