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JB: what is important in math . . . ?

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Our contributor JB asked to have a conversation on what is important in Mathematics, especially Math education.

I shared some thoughts.

>>Why not, let’s just do that, follow it up and see where it goes?

For instance, I think a key insight is to find a useful, powerful definition of what mathematics is. If we understand what it is we are exploring, it may give us a deeper, richer view on how we may understand and apply it. And for this, I have come to the view that an adaptation of a view I was taught by my very first uni prof is key:

Math is [the study of] the logic of structure and quantity.

That, is, there are two aspects, first, the substance of a certain field of reality: it forms a coherent framework of largely abstract structures and quantities. Coherence, being the gateway to the logic that guides our reasoning, and turns on the premise that realities are so together, thus accurate descriptions of said realities — truths — must equally fit with one another as they must also fit with realities. This means, rational thought is a main tool (and increasing our power of rational thought is a key motive and end) of Mathematics.

Further to this, I see a key application of the logic of being.For, key Mathematical entities, while abstract, are necessary, framework components of any possible world. Which immediately gives them enormous power and depth, as well as being a source of the aesthetic pleasure excited by well done Mathematics — its beauty. Order, intricacy, organising principles reflecting verisimilitude. So, Mathematics can be enriching, enjoyable and en-noble-ing. All of which are highly relevant to education and praxis. Also, the involvement of the appearance and substance of truth (with logical accountability and duties of prudence) brings out an ethical dimension, the other side of axiology.

Mathematics is a value-rich environment.

For example, ponder the compact, powerfully integrative insights locked in Euler’s expression:

0 = 1 + e^i * π

Going beyond, I find that a survey of key structures such as von Neumann’s exploration of the natural counting numbers, N, will help flesh this out, also teaching us the style of creative, insightful exploration that draws out the insightful creativity you are seeking to promote:

{} –> 0
{0} –> 1
{0,1} –> 2
. . . [HUGE!]
{0,1,2, . . . } –> ω

From this we may rapidly access the “mirror-image” additive inverses, thus the Integers Z. Ratios bring us to the rationals, Q. Infinite continued convergent sums of rationals give us the reals, R. Complex numbers C come in as rotating vectors (which then extend to basis vectors, the ijk system, general vectors, quaternions, matrices, tensors thus also groups, rings, fields and algebras). The transfinite ordinals, transfinite hyperreals

and the catapult through 1/x gets us to infinitesimals, here 1/K.

The Surreals come knocking at the door.

Valid infinitesimals give us an insight into Calculus.

With this in hand as a structured survey, all sorts of gateways for exploration are open, including a sound appreciation of sets, mathematical foundations, topology and more. Worthwhile in itself but also obviously relevant to the Calculus you wish to explore. Also, pointing to the world of computing.

We then gain an insight on axiomatisation and how it is subtly shaped by exploration and discovery of key mathematical facts (especially, necessary entities present in the framework of any world). So, we see how axioms may need to be plausible and if well phrased allow us to spin out abstract logic-model worlds that may speak to this and other possible worlds. Where, computing allows us to use machines in that exploration. More broadly, modelling is seen as a powerful but potentially misleading approach. Thus, issues of validation and testing lurk.

We could go on, but I think we see a vision.

While I am at it, Mr Shallit’s sneer falls to the ground, once we see the reality of necessary entities in world frameworks, the relevance of truth, beauty, prudence and more as well as the power of mind to have insight, to intuit, to perceive and to draw insights that transcend the capabilities of inherently blind, dynamic-stochastic, GIGO-limited computational substrates. Reppert, again, draws out the point decisively:

. . . let us suppose that brain state A [–> notice, state of a wetware, electrochemically operated computational substrate], which is token identical to the thought that all men are mortal, and brain state B, which is token identical to the thought that Socrates is a man, together cause the belief [–> concious, perceptual state or disposition] that Socrates is mortal. It isn’t enough for rational inference that these events be those beliefs, it is also necessary that the causal transaction be in virtue of the content of those thoughts . . . [But] if naturalism is true, then the propositional content is irrelevant to the causal transaction that produces the conclusion, and [so]

we do not have a case of rational inference. In rational inference, as Lewis puts it, one thought causes another thought not by being, but by being seen to be, the ground for it. But causal transactions in the brain occur in virtue of the brain’s being in a particular type of state that is relevant to physical causal transactions.

Mathematics is an exercise of the human spirit, which points to that Spirit who is the greatest Mathematician of all. Manifest, in the Mathematical frameworks of our world. A point long since articulated by founders of modern science who saw themselves as seeking to think God’s creative and world-sustaining thoughts after him. >>

Thoughts? END

Comments
Not society, hazel. Academia.ET
August 26, 2019
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I know you are sure that such pervades society, but why can't you be more specific? Where in a high school or college math class would any hint of naturalism appear? How could teaching polynomials, or logs, or trig, or the product rule, or any of the vast numbers of topic we teach, even mention, much less impose naturalism. Why can't you give an example? Or is all you can do is offer your standard general indictments?hazel
August 26, 2019
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Hazel, there is a widespread imposition of what is (in the bad sense) an ideological orthodoxy. KFkairosfocus
August 26, 2019
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What imposition? You give no evidence whatsoever that math teachers are "imposing naturalism." Yes, math teachers have some opportunity to discuss real-world ethical issues that students might encounter as they start to use math in conjunction with real-world situations, and I think we agree that this is a good thing to incorporate into teaching. But math teachers themselves are not "imposing naturalism", and the teaching of pure math itself does not reference any particular perspective about the nature of math. Advanced students, or as an enrichment for regular students, may have an opportunity to learn about the philosophy of math at some point, but as a survey of various perspectives, not as a claim that one perspectrive is right or wrong. But that is a different matter than just teaching math. Ona daily basis, "naturalism", pro or con, does not come up at all in any way.hazel
August 26, 2019
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Hazel, you just gave some fairly relevant cases, as that imposition is currently undermining the core of knowledge and the framework for integrity. KFkairosfocus
August 26, 2019
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What I meant was that math teachers aren't teaching any particular ethical philosophy, any more than we are teaching any particular religious or philosophical one. Of course we teach, explicitly and implicitly, lots of ethical and other character principles; honesty (don't cheat on your work), responsibility, punctuality, engagement in learning etc. Also, most stats teachers talk about ways in which stats can be used to mislead: missing portions of axes, confusions about what probabilities means, absolute vs relative percent changes, poor sampling methods, etc, and illustrate these with real world examples. This is non-controversial. Also, yes indeed, college students should have some exposure to ethical situations associated with their field of study, including whole courses in some cases, such as medicine, business, environmental studies, etc.. It is kf's "imposition of naturalism" idea that I strongly object to. There is nothing in the teaching of basic math that has anything to do with "imposing naturalism."hazel
August 26, 2019
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BO'H: thanks for thoughts. I think the matter is that we cannot split up the problem. Yes, we believe the core of Mathematics including statistics is reasonably reliable, but that reflects the ethics of epistemology, a prudence, integrity and accountability issue. Similarly, it is advisable for educators -- this is our context -- to address the cognitive, affective and psychomotor domains (using a common framework). So, that figures don't lie but liars can figure is a relevant concern [and for much more than Statistics], as is the matter of due diligence on degree of warrant. Ethical considerations and maturation will need to be reinforced from multiple contexts, they will not thrive in an era inclined to hyperskeptical dismissal if they are neatly packaged away in a unit or special event isolated from the general technical part of studies. And that highlights how our isolation of the ethical in an era dominated by naturalism is counterproductive. KFkairosfocus
August 26, 2019
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kf -
Hazel, already above we looked at ethics in statistics. A simple, obvious case: bias, cherry picking, reproducibility of results etc.
They're not in the mathematical part of statistics, though. They're issues in science, and the application of mathematical statistics.Bob O'H
August 26, 2019
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It doesn’t show up at all in the general high school or college math classroom. I also don’t see what ethical issues show up.
There had better be some ethical issues, otherwise I'm going to feel a bit of a berk sending my grad students on an ethics course.Bob O'H
August 26, 2019
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Hazel, already above we looked at ethics in statistics. A simple, obvious case: bias, cherry picking, reproducibility of results etc. This bleeds over into what may one fairly infer and what risks will one take -- this happens to be relevant to ID but is much broader. Try debates over opinion polling and statistical norms. Questions on warrant for conclusions. We have debated axiomatisation and facts or truths. . Issues of integrity, prudence (so, diligence in warrant and on limitations) are ethical issues. Ethics of the true and fair view. Recognising the implications of Godel and the like are worldviews issues. The general naturalistic climate is an issue and more. KFkairosfocus
August 25, 2019
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It doesn't show up at all in the general high school or college math classroom. I also don't see what ethical issues show up. Unless you can give an example, I'll not bother any further response to your standard concerns about this topic.hazel
August 25, 2019
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Hazel, the imposition of naturalism (often dressed in the lab coat) is a general problem in our intellectual culture; including Math, its foundations, linked issues in philosophy of Math, logic etc. It also seeps out in education, and here, ethics is a relevant point. KFkairosfocus
August 25, 2019
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I just read a book about the history of infinity in mathematics. I don't see how it has been "downplayed": it's been a critical topic for centuries. I also had a long conversation with you about your notation ideas. I wound up seeing your point in ways, but again, I don't see how this has to do with any philosophical points about naturalism. I think you and kf are seeing an issue where there just isn't one.hazel
August 25, 2019
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Hazel - Naturalism appeared in mathematics as the downplay of infinities, and actually, in my opinion, led mathematics astray for a bit. See this article here.johnnyb
August 25, 2019
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kf, I see we agree on a lot of pedagogical ideas. However, I have no idea how the "subtle imposition of naturalism" can come up in a math class.hazel
August 25, 2019
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Hazel, thanks for thoughts. I think there is need for knowledge of content, insight on intellectual strategies, building up of intellectual skills. Also, cultivation of integrity, here truth, right reason [so, logic], prudence, justice. I would use Ponzi schemes as a case study on ethics of Math, likewise something on statistical manipulation. Cases on right use such as epidemiology and cholera in London may help. The Euler identity in its more usual form (and related ideas on rotating vectors) is a good case study on coherence. I would use it to set a context for the Godel result. Of course the rotating vectors view also gets us complex numbers without the fuss and bother, as a natural result. I would reduce the fuss and bother to a footnote, identifying the power of that vectors view in bridging to applications. Math labs and skills make sense. Something as simple as avoiding parallax errors counts. Likewise, learning to stabilise the hand by putting the little finger to rest on a work surface. Even, setting a point of pencil or compass where one wants it "on the tilt" then rolling upright. Practical measurement skills and the empirical link between calculation and observable fact count. Try, volume of a parabolic wine glass by solid of revolution to go with the cone. Doing the cone by calculus too, seeing how logic and empirical reality connect thus logic of being. Mechanics, astronomy, navigation as application contexts. For example the bridge from a graph of uniformly accelerated motion, to the classic Galilean results then drawing out kinetic energy is a powerful integrative exercise. So is simple ballistics (and computers can bring in air resistance). Exposure to foundations of computing. With JB's revelation of the free Mathematica with Raspberry Pi, use of computing instruments and mathematical software. Operating in a world where grading work and students by red X's on faulty calculations is increasingly irrelevant and outdated. I suggest, subtle imposition of naturalism is just as much a religious and/or ideological imposition as any other. Worldview + cultural agenda = ideology ideology + power = regime Consequences follow. KFkairosfocus
August 25, 2019
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JB, Thanks for thoughts. I agree, the core ideas in hyperreals are easy enough that we should teach students the main domains of number. Surreals as a construction are hard to grasp as presented, but as setting out the "zoo" of numbers, I see no reason why we cannot refer to them. The concept of legitimate infinitesimals re-opens some of the advantages the early pioneers had and used. Certainly, as to concepts. I also agree that the pretence of neutrality (while smuggling in naturalism) does a lot of harm. Including, robbing students of insights. I am also serious on the point that Mathematics as to praxis is a study of the logic of structure and quantity. Thus, key concepts, strategies and skills of reasoning need to be on the table, perhaps even a bit on the philosophy, foundations and ethics of Mathematics that brings out the challenges of accountability before and commitment to truth, right reason, integrity, justice. The dirty games played with statistics and finance, come to mind. Here, truth as accurate description of reality counts, so deliberately untrue and manipulative misrepresentations are destructive. Maybe, why Ponzi-type schemes fail as a case study? Similarly, the concept of modelling, building logic-model worlds and how some entities are framework to any world thus generally applicable will be relevant. Including, core Mathematical structures. Here, the gap between model and reality may be relevant too, but the power of simplified or rather artificial models can be helpful. This is a contact with physics and other sciences, engineering, computer science [virtual machines etc], management, economics. Something as simple as flat geometry vs surface of earth may open vistas. And more. KFkairosfocus
August 25, 2019
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KF - great topic! Glad you moved your comment to a full post. It deserved it. Hazel - I actually teach hyperreals in my high school intro calculus course. My book, Calculus from the Ground Up, is based on this. I've skimmed Knuth's surreal book, but don't totally understand them. Hyperreals are actually really easy and really cool. I've actually toyed with the idea of just teaching hyperreals as an extension to regular math, and just watch calculus magically fall out of it. I actually think that having opinionated books is more helpful for students. It helps them engage. We should teach students not to blindly trust textbook authors, but *engage* with them, and then allow textbook authors to be opinionated. That is where real learning and interaction take place. I also think that the infinite, generally, is a place where we really do need to teach high school students, because so much thinking is based on infinities. Most sets that are logically-defined are actually infinite. That is, "even numbers" are logically-defined. "Countries" is a logically-defined construct. There are not infinite *existing* countries, but the number of possible configurations which fit the construct is infinite. Going over Hilbert's Hotel and Cantor's diagonalization argument is a fun mind-blowing experience for high-schoolers, and it helps pave the way for understanding many of the arguments for design in the future.johnnyb
August 24, 2019
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I taught high school math (mostly geometry and Intro to Calculus) in a small semi-urban school district for many years, and also the first year of college calculus and college algebra for a while, so my thoughts here are primarily about college-bound high school students, including their first year of college math. FWIW, many students do not take calculus in college (taking rather college algebra and/or stats), and those that do often take an applied or business calc rather than the more rigorous engineering or math major track. I think there are three broad primary goals in teaching math: 1. Teach the conceptual theories of the various concepts. A part of this should be to teach an awareness of and appreciation for the way in which math is a logically coherent system which builds on basic premises and logical reasoning. The process of understanding the development of the concepts and using them in problem solving teaches logical problem solving skills, including that such involve following steps each of which can be logically supported. 2. Teach and develop skills in the various conceptual, algorithmic, and procedural skills needed to actually use math correctly. Some examples: recognize a quadratic equation when it appears in a problem and know how to solve in the most appropriate way, know how to solve an equation with fractional exponents, or know how to differentiate a rational function. This includes knowing when it is appropriate to do math by hand, with a calculator, a spreadsheet, or dedicated piece of equipment. This also includes being able to write one’s work clearly in a way that can be communicated to others. The students have to know how to do the math expecting of them correctly and expeditiously. 3. Teach a wide variety of ways that math can be applied to the real world. This is critical. Seeing that math can be applied is a motivation to learn it: some students are motivated by the beauty of the math itself, as described in 1) above, and some by just the satisfaction of being able to “do the math” correctly, as in 2) above, but for many applying math to situations they think might be important is what motivates and interests them so that they want to apply themselves in learning. Real-world applications provide a vehicle for students to apply all the conceptual understanding and skills they have learned in an organized, directed way. 4. I also think it is important to provide some history and philosophy of math along the way, but given the practical demands of so much curriculum to cover, this needs to be more of an enrichment area. For instance, I used to do a class on the history of the number system, leading up to complex numbers, culminating with Euler’s Identity e^(i*pi) = -1. I also used to do a class on the nature of math, teaching some about Platonic and non-Platonic views, and then using the question ”is math discovered or invented” as a springboard for a class discussion. I emphasized this was a perennial unsettled question, and that they might enjoy studying some philosophy in college. (Footnote: I also used to do a guest lecture in the high school College English class on Plato’s Parable of the Cave, with the same intention of just introducing them to a range of philosophical views about ontology and epistemology that they had had very little experience with.) Now a few responses to the OP and comments. 1. kf mentions hyppereal and surreal numbers, but I believe those concepts are justifiably extremely rare in the average calculus curriculum, even in the second and third years of calculus, which I took (long ago) but never taught. 2. It is not the place of a math teacher to offer particular religious or philosophical reflections about math as the correct ones, but rather, as described in 4) above, if addressed, to make the student aware of the general broad views on the topic. 3. I agree with SmartAZ that even a college-bound curriculum needs to include building skills with standard measuring instruments. For instance, I used to do a “math lab” where students computed the volume of a cone using calculus and then checked their work by pouring water into a measured beaker. I taught them how to use a simple calipers, how to account for the “dead space” at the end of a ruler, and many other measuring skills in this and similar other projects. Part of this is teaching them to think about the level of accuracy they can obtain, and take that into account when calculating final answers. 4. Needless to say, I highly disagree with Vmahuna. He seems to have no real conception about how important math is so many occupations. I will say, however, that it is true that many specific skills and concepts are not used after being taught in skill. Two responses to that: first students incorporate an understanding of concepts that are important for understanding the world as a citizen even if they never have to “do the math” again. For instance, once one learns about general types of curves relating to variables (linear, polynomial, exponential, trigonometric, etc.), they can see and understand different patterns in the changes they learn about in the real world. Second, as teachers we never know what student will go on to use what skills, so we have to teach broadly so everyone has the skills they need as their occupation become settled. Also, these days students will change as the get older, so knowing how to learn math, and being able to dig back about things they did learn once, can be criticalhazel
August 24, 2019
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LC, a surveyor is routinely using all sorts of Math up to spherical trig, all that stuff about haversines and other transcendentals they don't usually talk about in grade school or high school. It's a pity that Calculus (first step to Analysis) is so often so badly taught. But then, something like ballistics with air effects (a gateway to dynamics of flight) would be very politically incorrect today. That tale in a nutshell on the barn over the line is sad but telling, and of course is about triangle power. Yep, many mathematical entities and relationships are in the framework of this or any world, tied to logic of being. The beings in mathematics are those of structure and quantity. And insofar as duties of truth and right reason [= logic, a part of Math], prudence etc obtain, they are tied to how we are morally governed. Come to think of it the issue of integrity explicitly came up in just two courses I ever did, 6th form Physics and Finance -- both, heavy users of advanced topics in Math. But it is implicitly there all the time. I guess we are more willing to trust a programmer over in India somewhere we don't see than a live surveyor toting theodolite and maybe a calculator we do see. That says something. KFkairosfocus
August 24, 2019
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VM, for me, it is very different. KFkairosfocus
August 24, 2019
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Practically NOTHING learnt after grade school about Math is important.
Only if "grade school" means any and all levels of schooling.ET
August 24, 2019
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From David Berlinski’s Advent of the Algorithm: “Mathematicians have loved mathematics because, like the graces of which Sappho wrote, the subject has wrists like wild roses. If it is beauty that governs the mathematicians’ souls, it is truth and certainty that remind them of their duty. At the end of the nineteenth century, mathematicians anxious about the foundations of their subject asked themselves why mathematics was true and whether it was certain and to their alarm discovered that they could not say and did not know. Working mathematicians continued to work at mathematics, of course, but they worked at what they did with the sense that some sinister figure was creeping up the staircase of events.” As a land surveyor I established the physical boundaries of municipalities and private property before the GPS system existed. When you’re engaged in using measuring instruments and math to establish the structure and quantity of someone’s land they take an interest in the results. You can wave your State license all you want it doesn’t overcome the emotions that result when someone’s grandfather built a mule barn on someone else’s property but now it and the land it’s on has to go. You can explain the math and the methods used to arrive at your result and have a court uphold the survey but that won’t protect your trucks and equipment from vandalism, either. I have a feeling that if the property boundary were instead established by a modern GPS system, that is, by a blind GIGO-limited computational substrate, those particular survey results might have been more easily accepted. I have gone back to check this and some other results I arrived at over 30 years ago using modern GPS equipment and it turns out my results were wrong. By 2 centimeters over a distance of 4500 meters; less than the width of a fence post. That personal sinister figure was stopped on its climb up the steps. When I was in school sweating my way through calculus courses I never had any idea what it would be good for in the real world. School did not teach me that knowledge of math was conducive to becoming anything other than, say, a math professor at some State college, if I was lucky, and that’s a shame. It was just something you had to get through before the finish line. There is a gap between educational institutions and the rest of the world in many things, even more so these days where cultural agenda seems to be the prime focus regardless of the field of study. I think that math is embedded in the substrate of our world. KF is much better at explaining why mathematical logic explains our duties to the truth, right reason, prudence, sound conscience and justice. The world root is not just causally adequate to our physical world with computational entities but it also grounds responsible rational free morally governed minds. This points to a necessary, inherently good and utterly wise being responsible for all we see.LoneCycler
August 24, 2019
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Practically NOTHING learnt after grade school about Math is important. You're sure not going to find any USE for it. After all, TV commercials regularly tell us that the product does "400% MORE" than the competitors. Does ANYONE know what that means? I worked with a woman who had earned a BS in Math. It had ABSOLUTELY no value in government processes run by edicts and impenetrable computer programs. Also, our job was being done by people with no college education at all, and when our "intern" program failed to show that 20 years of following the rules could be successfully replaced by 4 years of college, The Government went back to filling the positions from pools of "warehouse clerks", who are not known for their THINKING about generalized, as opposed to today's SPECIFIC, problems. I read some years back that the Ebonics approach to what passes as Logic and grammar GUARANTEES that no Ebonics speaker will EVER be able to make a coherent statement about number juggling. As with junk like Physics, there is some TEENY number (half of 1%?) of individuals who should be trained in the Ancient Magic to keep the flame alive, but there ain't no point in attempting to DISCUSS "Whither the Mathematics" in public.vmahuna
August 24, 2019
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Get a ruler in your hands. Measure things until you start to understand how a ruler works. Measure some stuff and figure out where the center is. Say you measure a book and it's 7/8" thick. You look at your ruler and see that every eighth is divided into two sixteenths, so obviously half of 7/8" is going to be 7/16". If you write that out you have 1/2 x 7/8 = 7/16. And you notice that 1/2 is divided into 2/4 and then into 4/8 and so on, so you can convert anything to anything by multiplying all the numbers on top and then all the numbers on bottom. Other rulers are divided into 10 and 100 parts. But an inch is still an inch, so anything on one ruler can be translated to the other ruler. A half inch on one ruler is 5/10 or 50/100 on the other. An eighth inch is just 12.5 marks when you have 100 marks per inch. A metric ruler divides an inch into 25.4 parts, so a half inch would be 12.7 of those parts. Pretty simple, isn't it? Practice this a bit and people will think you went to wizard school.SmartAZ
August 24, 2019
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JB: what is important in math . . . ?kairosfocus
August 24, 2019
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