## Reading the Comics, November 7, 2018: Shorthand and Reruns Edition

There’s two types of comics for the second of last week’s review. There’s some strips that are reruns. There’s some that just use mathematics as a shorthand for something else. There’s four strips in all.

John Deering’s Strange Brew for the 6th uses mathematics as shorthand for demonstrating intelligence. There’s no making particular sense out of the symbols, of course. And I’d think it dangerous that Lucky seems to be using both capital X and lowercase x in the same formula. There’s often times one does use the capital and lowercase versions of a letter in a formula. This is usually something like “x is one element of the set X, which is all the possible candidates for some thing”. In that case, you might get the case wrong, but context would make it clear what you meant. But, yes, sometimes there’s no sensible alternative and then you have to be careful.

Randy Glasbergen’s Glasbergen Cartoons for the 6th uses mathematics as shorthand for a hard subject. It’s certainly an economical notation. Alas, you don’t just learn from your mistakes. You learn from comparing your mistakes to a correct answer. And thinking about why you made the mistakes you did, and how to minimize or avoid those mistakes again.

So how would I do this problem? Well, carrying out the process isn’t too hard. But what do I expect the answer to be, roughly? To me, I look at this and reason: 473 is about 500. So 473 x 17 is about 500 x 17. 500 x 17 is 1000 times eight-and-a-half. So start with “about 8500”. That’s too high, obviously. I can do better. 8500 minus some correction. What correction? Well, 473 is roughly 500 minus 25. So I’ll subtract 25 times 17. Which isn’t hard, because 25 times 4 is 100. So 25 times 17? That’s 25 times 16 plus 25 times 1. 25 times 16 is 100 times 4. So 25 times 17 is 425. 8500 minus 425 is 8075. I’m still a bit high, by 2 times 17. 2 times 17 is 34. So subtract 34 from 8075: it should be about 8041.

John Zakour and Scott Roberts’s Maria’s Day for the 7th is a joke built on jargon. Every field has its jargon. Some of it will be safely original terms: people’s names (“Bessel function”) or synthetic words (“isomorphism”) that can’t be easily confused with everyday language. But some of it will be common terms given special meaning. “Right” angles and “right” triangles. “Normal” numbers. “Group”. “Right” as a description for angles and triangles goes back a long way, at least to — well, Merriam-Webster.com says 15th century. But EtymologyOnline says late 14th century. Neither offers their manuscripts. I’ll chalk it up to differences in how they interpret the texts. And possibly differences in whether they would count, say, a reference to “a right angle” written in French or German rather than in English directly.

Richard Thompson’s Richard’s Poor Almanac for the 7th has been run before. It references the Infinite Monkey Theorem. The monkeys this time around write up a treasury of Western Literature, not merely the canon of Shakespeare. That’s at least as impressive a feat. Also, while this is a rerun — sad to say Richard Thompson died in 2016, and was forced to retire from drawing before that — his work was fantastic and deserves attention.

This and every Reading the Comics post should be at this link. Essays discussing topics raised by Strange Brew are at this link. The essays discussing Glasbergen Cartoons are at this link. Essays which mention Maria’s Day, are at this link. And essays featuring Richard’s Poor Almanac are at this link.

My Fall 2018 Mathematics A-To-Z averages two new posts a week, through the end of December. Thanks again for reading.

## Reading the Comics, October 30, 2018: I Spot An Error Edition

The edition title says it all. Comic Strip Master Command sent me enough strips the past week for two editions and I made an unhappy discovery about one of the comics in today’s.

Dave Coverly’s Speed Bump for the 28th is your anthropomorphic-numerals joke for the week. We get to know the lowest common denominator from fractions. It’s easier to compute anything with a fraction in it if you can put everything under a common denominator. But it’s also — usually — easier to work with smaller denominators than larger ones. It’s always okay to multiply a number by 1. It may not help, but it can always be done. This has the result of multiplying both the numerator and denominator by the same number. So suppose you have something that’s written in terms of sixths, and something else written in terms of eighths. You can multiply the first thing by four-fourths, and the second thing by three-thirds. Then both fractions are in terms of 24ths and your calculation is, probably, easier.

So this strip is the rare one where I have to say the joke doesn’t work on mathematical grounds. Coverly was mislead by the association between “lowest” and “smallest”. 2 is going to be the lowest common denominator very rarely. Everything in the problem needs to be in terms of even denominators to start with, and even that won’t guarantee it. I hate to do that, since the point of a comic strip is humor and getting any mathematics right is a bonus. But in this case, knowing the terminology shatters the joke. Coverly would have a mathematically valid joke were 9 offering the consolation “you’re not always the greatest common divisor”, the largest number that goes into a set of numbers. But nobody thinks being called the “greatest” anything ever needs consolation, so the joke would fail all but mathematics class.

Randy Glasbergen’s Glasbergen Cartoons for the 29th is a joke of the why-learn-mathematics model. “Because we always have done this” is not a reason compelling by the rules of deductive logic. It can have great practical value. Experience can encode things which are hard to state explicitly, or to untangle from one another. And an experienced system will have workarounds for the most obvious problems, ones that a new system will not have. And any attempt at educational reform, however well-planned or meant, must answer parents’ reasonable question of why their child should be your test case.

I do sometimes see algebra attacked as being too little-useful for the class time given. I could see good cases made for spending the time on other fields of mathematics. (Probability and statistics always stands out as potentially useful; the subjects were born from things people urgently needed to know.) I’m not competent to judge those arguments and so shall not.

Carl Skanberg’s That New Carl Smell for the 29th is a riff on jokes about giving more than 100%. Interpreting this giving-more-than-everything as running a deficit is a reasonable one. I’ve given my usual talk about “100% of what?” enough times now; I don’t need to repeat it until I think of something fresh to say.

Jeffrey Caulfield and Alexandre Rouillard’s Mustard and Boloney for the 30th uses mathematics — story problems, specifically — as icons of intelligence. I can’t speak to the Mensa experience, but intellectual types trying to out-do each other? Yes, that’s a thing that happens. I mostly dodge attempts to put me to a fun mathematics puzzle. I’m embarrassed by how long it can take me to actually do one of these, when put on the spot. (I have a similar reaction to people testing my knowledge of trivia in the stuff I actually do know a ridiculous amount about.) Mostly I hope Dave Coverly doesn’t think I’m being this kid.

All of the Reading the Comics posts should be at this link. Essays that include Speed Bump are at this link. I don’t usually have a problem with it. Essays discussing Glasbergen Cartoons should be at this link. They won’t include Glasbergen’s longrunning The Better Half comic, which as far as I can find only ever appeared here the one time anyway. It’s a new tag anyway. Essays with a mention of That New Carl Smell are at this link. It’s a new tag, though, so give it some time if you want to read anything else. Essays with a mention of Mustard and Boloney are at this link. And my Fall 2018 Mathematics A-To-Z should continue for the rest of this calendar year. And it is open for requests for more of the alphabet. Thanks for reading.