

This week’s collection of mathematics-themed comic strips includes one of the best examples of using mathematics in real life, because it describes how to find your position if you’re lost in, in this case, an uncharted island. I’m only saddened that I couldn’t find a natural way to work in how to use an analog watch as a makeshift compass, so I’m shoehorning it in up here, as well as pointing out that if you don’t have an analog clock to use, you can still approximate it by drawing the hands of the clock on a sheet of paper and using that as a pretend watch, and there is something awesome about using a sheet of paper with the time drawn on it as a way to finding north.

Dave Whamond’s Reality Check (January 12) is a guru-on-the-mountain joke, explaining that the answers to life are in the back of the math book. It’s certainly convention for a mathematics book, at least up through about Intro Differential Equations, to include answers to the problems, or at least a selection of problems, in the back, and on reflection it’s a bit of an odd convention. You don’t see that in, say, a history book even where the questions can be reduced to picking out trivia from the main text. I suppose the math-answers convention reflects an idea that there’s a correct way to go about solving a problem, and therefore, you can check whether you picked the correct way and followed it correctly with no more answer than a printed “15/2” as guide. In this way, I suppose, a mathematics textbook can be self-teaching — at least, the eager student can do some of her own pass/fail grading — which was probably invaluable back in the days when finding a skilled mathematics teacher was so much harder than it is today.

Ruben Bolling’s Super-Fun-Pak-Comix (January 12) reruns another excerpt from Chaos Butterfly, this time showing an even more extreme dependence of deterministic processes on infinitesimally tiny influences. I don’t know how the butterfly’s flap can cause a cement truck accident, but we do live in a complicated world.

Randy Glasbergen’s Thin Lines (January 12) uses a string of conversions from one base to another and throwing in factors arbitrarily to make an achievement (that’s already a pretty impressive one, by the way) sound bigger. This is shown as an example of just fooling oneself, but accounting for anything once it gets past a terribly simple example can require a lot of calculating, and much of it can be disputed. For example, in attempts to create energy-generating nuclear fusion, to know if one’s succeeded, one has to work out what all the sources of input energy and output energy are, and these can include some pretty ethereal stuff, exotic stuff like how much heat transferred by magnetic fields goes into phase changes in the materials lining the chamber. If your estimates of these quantities are bad you can conclude you’ve done something you haven’t, or vice-versa. Still, losing five pounds in a week is impressive enough, it doesn’t need to be exaggerated.

Bunny Hoest and John Reiner’s The Lockhorns (January 13) mentions KenKen as the sort of challenging recreational mathematical activity that of course the two can’t imagine the other doing well. KenKen, invented by Tetsuya Miyamoto in 2004 (says Wikipedia), adds to the complexity of sudoku by blocking out sections of the grid and requiring the numbers placed in each block satisfy some additional requirement, such as that they add up to 10, or that multiplied together they equal 30. This adds arithmetic to the challenge, but it is fundamentally a logic problem, searching out arrangements of digits which do not contradict any of the requirements about not repeating digits within a row or column or block and making whatever arithmetic operation is in the block be satisfied. I admit this is a bit more work than I feel like doing recreationally these days, but I get the appeal.

'Forget KenKen ... Leroy has trouble figuring out the comics.'

Bunny Hoest and John Reiner’s The Lockhorns for the 13th of January, 2015, in a panel that isn’t at all teasing the Fourth Wall.

Bill Amend’s FoxTrot Classics (January 13) gives us Marcus and Jason in a showdown of reciting the digits of pi backwards, which has obvious problems in getting things started. I’m honestly surprised they find this a challenging enough problem to do, but it’s been a long while since I was ten years old.

Keith Tutt and Daniel Saunders’s Lard’s World Peace Tips (January 13) gives us a little sloppy-arithmetic joke and gives away that the writers hew to the British convention for abbreviating “mathematics”. Many people have wondered why Americans say “math” and British (and many Commonwealth nations; I forget which English-speaking Canada prefers) say “maths”, and the answer seems to always disappoint: there’s no particular reason, it just worked out that way. I have been coming around to seeing the logic of saying “maths”, as a way of subtly reinforcing that there are many different kinds of things which are all mathematics and the field can be usefully seen as many different kinds of subject united by some attitude, but since I’m from New Jersey I still feel like I’m affecting a pose by saying “maths”.

Paige Braddock’s Jane’s World (January 15) includes Jane and some friends stranded by a light plane crash somewhere off the Florida coast; Jane’s horrified to learn that working out their location is going to require a lot of mathematics. Working out one’s position has always required mathematics; it might be the greatest practical use of mathematics, if commerce and finance are ignored. One’s latitude — distance north or south of the equator — can be worked out approximately by observing where Polaris is, relative to the horizon; the angle between the star and the horizon is the angle between the equator and your position. (As I say, approximately; to be more exact you have to account for Polaris not actually being quite above the north pole, and if you’re in the southern hemisphere you have to use other references.) Longitude can be worked out just as Jill describes in the strip: a difference in local time between your position and the local time of some reference point tells you how far east, or west, of the reference point you are. I am skeptical that this could be worked out reasonably accurately given the hardware the characters have on hand, but it’s possible that Jill is figuring that working on this specific problem like this will keep everyone from panicking at being stranded by a plane crash on some unknown island. And, heck, I haven’t tried doing this myself and don’t know what kind of emergency equipment a small recreational plane would have, so maybe I’m just being pessimistic.

John Zakour and Scott Roberts’s Maria’s Day (January 16) shows Maria having a superhero fantasy that’s overcome by the challenge of division. The curious thing is it isn’t long division: I understand why long division is challenging, since it depends on making a guess and then refining it. Simple division like this can be as simple as following a rule and getting inevitably to the right answer.

Lincoln Peirce’s Big Nate: First Class (January 16, and a rerun of the comic strip’s origin) shows Nate’s dad has forgotten his geometry vocabulary since he left school. I’m not sure of a mnemonic to help him with radius versus diameter, but one key to remembering circumference is that “circum” at the front. The root means “around”, and you can see in it words like “circumspect” and “circumnavigate”, evoking the idea of going around a thing.

I suppose the “dia” at the start of “diameter” might be seen as suggesting two, and the diameter is twice the radius. But I’m not sure that would help keep the relationship between radius and diameter clear since, after all, you could misremember the rule as “two diameters make a radius”. A good mnemonic has to be hard to remember wrong. For example — something Robert Benchley observed — the key words ought to be set in a rhyme so they can’t fit the wrong way.

J C Duffy’s The Fusco Brothers (January 17) does a panhandler’s sign that is also a fair little pre-algebra problem, in case you need one for your classes.

John Deering’s Strange Brew (January 17) is another entry in the lives of anthropomorphic numerals.

Of this collection of comics I’d say that Jane’s World was the most interesting, since it gets at a nice meaty subject with plenty of history behind it. None of them were really laugh-out-loud funny, although the silly logic of the FoxTrot problem and the gentle understated whimsy of Lard’s World Peace Tips appealed there.