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  • Joseph Nebus 6:00 pm on Sunday, 23 April, 2017 Permalink | Reply
    Tags: , , , Edison Lee, , Lug Nuts, , story problems,   

    Reading the Comics, April 18, 2017: Give Me Some Word Problems Edition 


    I have my reasons for this installment’s title. They involve my deductions from a comic strip. Give me a few paragraphs.

    Mark Anderson’s Andertoons for the 16th asks for attention from whatever optician-written blog reads the comics for the eye jokes. And meets both the Venn Diagram and the Mark Anderson’s Andertoons content requirements for this week. Good job! Starts the week off strong.

    Lincoln Pierce’s Big Nate: First Class for the 16th, rerunning the strip from 1993, is about impossibly low-probability events. We can read the comic as a joke about extrapolating a sequence from a couple examples. Properly speaking we can’t; any couple of terms can be extended in absolutely any way. But we often suppose a sequence follows some simple pattern, as many real-world things do. I’m going to pretend we can read Jenny’s estimates of the chance she’ll go out with him as at all meaningful. If Jenny’s estimate of the chance she’d go out with Nate rose from one in a trillion to one in a billion over the course of a week, this could be a good thing. If she’s a thousand times more likely each week to date him — if her interest is rising geometrically — this suggests good things for Nate’s ego in three weeks. If she’s only getting 999 trillionths more likely each week — if her interest is rising arithmetically — then Nate has a touch longer to wait before a date becomes likely.

    (I forget whether she has agreed to a date in the 24 years since this strip first appeared. He has had some dates with kids in his class, anyway, and some from the next grade too.)

    J C Duffy’s Lug Nuts for the 16th is a Pi Day joke that ran late.

    Jef Mallett’s Frazz for the 17th starts a little thread about obsolete references in story problems. It’s continued on the 18th. I’m sympathetic in principle to both sides of the story problem debate.

    Is the point of the first problem, Farmer Joe’s apples, to see whether a student can do a not-quite-long division? Or is it to see whether the student can extract a price-per-quantity for something, and apply that to find the quantity to fit a given price? If it’s the latter then the numbers don’t make a difference. One would want to avoid marking down a student who knows what to do, and could divide 15 cents by three, but would freeze up if a more plausible price of, say, $2.25 per pound had to be divided by three.

    But then the second problem, Mr Schad driving from Belmont to Cadillac, got me wondering. It is about 84 miles between the two Michigan cities (and there is a Reed City along the way). The time it takes to get from one city to another is a fair enough problem. But these numbers don’t make sense. At 55 miles per hour the trip takes an awful 1.5273 hours. Who asks elementary school kids to divide 84 by 55? On purpose? But at the state highway speed limit (for cars) of 70 miles per hour, the travel time is 1.2 hours. 84 divided by 70 is a quite reasonable thing to ask elementary school kids to do.

    And then I thought of this: you could say Belmont and Cadillac are about 88 miles apart. Google Maps puts the distance as 86.8 miles, along US 131; but there’s surely some point in the one town that’s exactly 88 miles from some point in the other, just as there’s surely some point exactly 84 miles from some point in the other town. 88 divided by 55 would be another reasonable problem for an elementary school student; 1.6 hours is a reasonable answer. The (let’s call it) 1980s version of the question ought to see the car travel 88 miles at 55 miles per hour. The contemporary version ought to see the car travel 84 miles at 70 miles per hour. No reasonable version would make it 84 miles at 55 miles per hour.

    So did Mallett take a story problem that could actually have been on an era-appropriate test and ancient it up?

    Before anyone reports me to Comic Strip Master Command let me clarify what I’m wondering about. I don’t care if the details of the joke don’t make perfect sense. They’re jokes, not instruction. All the story problem needs to set up the joke is the obsolete speed limit; everything else is fluff. And I enjoyed working out variation of the problem that did make sense, so I’m happy Mallett gave me that to ponder.

    Here’s what I do wonder about. I’m curious if story problems are getting an unfair reputation. I’m not an elementary school teacher, or parent of a kid in school. I would like to know what the story problems look like. Do you, the reader, have recent experience with the stuff farmers, drivers, and people weighing things are doing in these little stories? Are they measuring things that people would plausibly care about today, and using values that make sense for the present day? I’d like to know what the state of story problems is.

    Lee: 'I'm developing a new theory about avocado intelligence.' Joules: 'You can't be serious.' Lee: 'Avocado, what is the square root of 8,649?' Avocado: 'That's easy. It's 92?' Lee: 'Wrong. It's 93.' Joules: 'See? It's just a dumb piece of fruit.' Lee: 'I honestly thought I was on to something.'

    John Hambrock’s The Brilliant Mind of Edison Lee for the 18th of April, 2017. Before you ask what exactly the old theory of avocado intelligence was remember that Edison Lee’s lab partner there is a talking rat. Just saying.

    John Hambrock’s The Brilliant Mind of Edison Lee for the 18th uses mental arithmetic as the gauge of intelligence. Pretty harsly, too. I wouldn’t have known the square root of 8649 off the top of my head either, although it’s easy to tell that 92 can’t be right: the last digit of 92 squared has to be 4. It’s also easy to tell that 92 has to be about right, though, as 90 times 90 will be about 8100. Given this information, if you knew that 8,649 was a perfect square, you’d be hard-pressed to think of a better guess for its value than 93. But since most whole numbers are not perfect squares, “a little over 90” is the best I’d expect to do.

     
  • Joseph Nebus 6:00 pm on Sunday, 16 April, 2017 Permalink | Reply
    Tags: Amanda the Great, , , , , , , Gentle Creatures, , , Skin Horse, story problems, Strange Brew,   

    Reading the Comics, April 15, 2017: Extended Week Edition 


    It turns out last Saturday only had the one comic strip that was even remotely on point for me. And it wasn’t very on point either, but since it’s one of the Creators.com strips I’ve got the strip to show. That’s enough for me.

    Henry Scarpelli and Craig Boldman’s Archie for the 8th is just about how algebra hurts. Some days I agree.

    'Ugh! Achey head! All blocked up! Throbbing! Completely stuffed!' 'Sounds like sinuses!' 'No. Too much algebra!'

    Henry Scarpelli and Craig Boldman’s Archie for the 8th of April, 2017. Do you suppose Archie knew that Dilton was listening there, or was he just emoting his fatigue to himself?

    Ruben Bolling’s Super-Fun-Pak Comix for the 8th is an installation of They Came From The Third Dimension. “Dimension” is one of those oft-used words that’s come loose of any technical definition. We use it in mathematics all the time, at least once we get into Introduction to Linear Algebra. That’s the course that talks about how blocks of space can be stretched and squashed and twisted into each other. You’d expect this to be a warmup act to geometry, and I guess it’s relevant. But where it really pays off is in studying differential equations and how systems of stuff changes over time. When you get introduced to dimensions in linear algebra they describe degrees of freedom, or how much information you need about a problem to pin down exactly one solution.

    It does give mathematicians cause to talk about “dimensions of space”, though, and these are intuitively at least like the two- and three-dimensional spaces that, you know, stuff moves in. That there could be more dimensions of space, ordinarily inaccessible, is an old enough idea we don’t really notice it. Perhaps it’s hidden somewhere too.

    Amanda El-Dweek’s Amanda the Great of the 9th started a story with the adult Becky needing to take a mathematics qualification exam. It seems to be prerequisite to enrolling in some new classes. It’s a typical set of mathematics anxiety jokes in the service of a story comic. One might tsk Becky for going through university without ever having a proper mathematics class, but then, I got through university without ever taking a philosophy class that really challenged me. Not that I didn’t take the classes seriously, but that I took stuff like Intro to Logic that I was already conversant in. We all cut corners. It’s a shame not to use chances like that, but there’s always so much to do.

    Mark Anderson’s Andertoons for the 10th relieves the worry that Mark Anderson’s Andertoons might not have got in an appearance this week. It’s your common kid at the chalkboard sort of problem, this one a kid with no idea where to put the decimal. As always happens I’m sympathetic. The rules about where to move decimals in this kind of multiplication come out really weird if the last digit, or worse, digits in the product are zeroes.

    Mel Henze’s Gentle Creatures is in reruns. The strip from the 10th is part of a story I’m so sure I’ve featured here before that I’m not even going to look up when it aired. But it uses your standard story problem to stand in for science-fiction gadget mathematics calculation.

    Dave Blazek’s Loose Parts for the 12th is the natural extension of sleep numbers. Yes, I’m relieved to see Dave Blazek’s Loose Parts around here again too. Feels weird when it’s not.

    Bill Watterson’s Calvin and Hobbes rerun for the 13th is a resisting-the-story-problem joke. But Calvin resists so very well.

    John Deering’s Strange Brew for the 13th is a “math club” joke featuring horses. Oh, it’s a big silly one, but who doesn’t like those too?

    Dan Thompson’s Brevity for the 14th is one of the small set of punning jokes you can make using mathematician names. Good for the wall of a mathematics teacher’s classroom.

    Shaenon K Garrity and Jefferey C Wells’s Skin Horse for the 14th is set inside a virtual reality game. (This is why there’s talk about duplicating objects.) Within the game, the characters are playing that game where you start with a set number (in this case 20) tokens and take turn removing a couple of them. The “rigged” part of it is that the house can, by perfect play, force a win every time. It’s a bit of game theory that creeps into recreational mathematics books and that I imagine is imprinted in the minds of people who grow up to design games.

     
  • Joseph Nebus 6:00 pm on Tuesday, 13 September, 2016 Permalink | Reply
    Tags: , , , story problems   

    Reading the Comics, September 10, 2016: Finishing The First Week Of School Edition 


    I understand in places in the United States last week wasn’t the first week of school. It was the second or third or even worse. These places are crazy, in that they do things differently from the way my elementary school did it. So, now, here’s the other half of last week’s comics.

    Zach Weinersmith’s Saturday Morning Breakfast Cereal presented the 8th is a little freak-out about existence. Mathematicians rely on the word “exists”. We suppose things to exist. We draw conclusions about other things that do exist or do not exist. And these things that exist are not things that exist. It’s a bit heady to realize nobody can point to, or trap in a box, or even draw a line around “3”. We can at best talk about stuff that expresses some property of three-ness. We talk about things like “triangles” and we even draw and use representations of them. But those drawings we make aren’t Triangles, the thing mathematicians mean by the concept. They’re at best cartoons, little training wheels to help us get the idea down. Here I regret that as an undergraudate I didn’t take philosophy courses that challenged me. It seems certain to me mathematicians are using some notion of the Platonic Ideal when we speak of things “existing”. But what does that mean, to a mathematician, to a philosopher, and to the person who needs an attractive tile pattern on the floor?

    Cathy Thorne’s Everyday People Cartoons for the 9th is about another bit of the philosophy of mathematics. What are the chances of something that did happen? What does it mean to talk about the chance of something happening? When introducing probability mathematicians like to set it up as “imagine this experiment, which has a bunch of possible outcomes. One of them will happen and the other possibilities will not” and we go on to define a probability from that. That seems reasonable, perhaps because we’re accepting ignorance. We may know (say) that a coin toss is, in principle, perfectly deterministic. If we knew exactly how the coin is made. If we knew exactly how it is tossed. If we knew exactly how the air currents would move during its fall. If we knew exactly what the surface it might bounce off before coming to rest is like. Instead we pretend all this knowable stuff is not, and call the result unpredictability.

    But about events in the past? We can imagine them coming out differently. But the imagination crashes hard when we try to say why they would. If we gave the exact same coin the exact same toss in the exact same circumstances how could it land on anything but the exact same face? In which case how can there have been any outcome other than what did happen? Yes, I know, someone wants to rush in and say “Quantum!” Say back to that person, “waveform collapse” and wait for a clear explanation of what exactly that is. There are things we understand poorly about the transition between the future and the past. The language of probability is a reminder of this.

    Hilary Price’s Rhymes With Orange for the 10th uses the classic story-problem setup of a train leaving the station. It does make me wonder how far back this story setup goes, and what they did before trains were common. Horse-drawn carriages leaving stations, I suppose, or maybe ships at sea. I quite like the teaser joke in the first panel more.

    Caption: Lorraine felt like God was always testing her. She's in a car. God's voice calls, 'A train leaves the station travelling east at 70 mph. At the same time ...' The intro panel, 'The Journey', features Lorraine thinking, 'Shouldn't you be busy rooting for some pro athlete?'

    Hilary Price’s Rhymes With Orange for the 10th of September, 2016. 70 mph? Why not some nice easy number like 60 mph instead? God must really be testing.

    Dan Collins’s Looks Good on Paper for the 10th is the first Möbius Strip joke we’ve had in a while. I’m amused and I do like how much incidental stuff there is. The joke would read just fine without the opossum family crossing the road, but it’s a better strip for having it. Somebody in the comments complained that as drawn it isn’t a Möbius Strip proper; there should be (from our perspective) another half-twist in the road. I’m willing to grant it’s there and just obscured by the crossing-over where the car is, because — as Collins points out — it’s really hard to draw a M&oum;bius Strip recognizably. You try it, and then try making it read cleanly while there’s, at minimum, a road and a car on the strip. That said, I can’t see that the road sign in the lower-left, by the opossums, is facing the right direction. Maybe for as narrow as the road is it’s still on a two-lane road.

    Tom Toles’s Randolph Itch, 2 am rerun for the 10th is an Einstein The Genius comic. It felt familiar to me, but I don’t seem to have included it in previous Reading The Comics posts. Perhaps I noticed it some week that I figured a mere appearance of Einstein didn’t rate inclusion. Randolph certainly fell asleep while reading about mathematics, though.

    It’s popular to tell tales of Einstein not being a very good student, and of not being that good in mathematics. It’s easy to see why. We’d all like to feel a little more like a superlative mind such as that. And Einstein worked hard to develop an image of being accessible and personable. It fits with the charming absent-minded professor image everybody but forgetful professors loves. It feels dramatically right that Einstein should struggle with arithmetic like so many of us do. It’s nonsense, though. When Einstein struggled with mathematics, it was on the edge of known mathematics. He needed advice and consultations for the non-Euclidean geometries core to general relativity? Who doesn’t? I can barely make my way through the basic notation.

    Anyway, it’s pleasant to see Toles holding up Einstein for his amazing mathematical prowess. It was a true thing.

     
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