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Comment by jclaassen | Hacker News Reader

Am I just being an engineer, or is the math way easier than the rest of this test?

I teach mathematics at a community college and I can tell you that for most people the mathematics on the test is hard. Our course with the largest number of students is on arithmetic and the students just don't comprehend fractions. They can't even comprehend how to convert a decimal to a percent. Especially when given a problem like:

Conver 0.25% to a decimal. That really throws them off.

While I understand this question, I think it is a bit of a trick. I think it would make more sense to ask them to convert 1.25% to a decimal, or any percentage that did not have leading zeros.

I think it is important for one to be able to follow instructions even if they might appear counterintuitive. The rule for conversion is to divide by 100. It doesn't matter what percentage I give you; always divide by 100. It's fairly straightforward but many people are unable to do so in the case of 0.25%. They expect the answer to be 25.

It's not a trick. It requires critical thinking skills, and that a student internalizes concepts like percentages, decimals and fractions.

I've heard from folks in retail finance that large segments of American society do not understand the concept of an interest rate. Everything is just "what is my monthly payment?"

I talked to a fellow CS major Thursday evening and he said he hated all the math involved with the CS program, and that he' failed Pre-Calculus & Trigonometry I three times. This came out after he was complaining about his discrete computational structures class being "nothing but proofs".

If you don't like the math, why get a CS degree? Get a physical science degree and learn how to code on your own time.

Physical science probably won't be much better if you don't like math. Remember, "The book of nature is written in the language of mathematics". Heck, be a humanities major and learn to code, it's not like computers only work for people with technical degrees (though I suspect the training in rigorous thinking helps).

After a lecture and doing several examples I a majority of my college algebra students couldn't do this problem.

You have a house that you bought for $120,000. You sell the house for $173,000 and the real estate commission is 6%. As the seller of the house you have to pay the real estate commission. The real estate commission is an expense and is not counted as part of your profit from the sale of the house. You have to pay a tax of 30% on the profit from the sale of the house. How much tax is paid?

They just couldn't grasp that the real estate commission was not part of their profit. I got the impression that the students believe that the real estate commission is not an expense.

I do believe that a large percentage of society does not understand interest.

Have a look at the UK's STEP mathematics papers. They're the toughest school-level exams we have, used as entrance tests for a handful of degree courses. There are three papers each year, in increasing level of difficulty and assumed knowledge, and each candidate takes papers I and II or papers II and III.

http://www.admissionstests.cambridgeassessment.org.uk/adt/st...

Thanks for sharing that... I found the paper from 1998 that I took... I don't remember how to answer any of the questions anymore which is pretty scary given I did OK back then!!

Some problems are quite fun, but they spoil them with clues -- it does not feel like solving, more like explaining the solution.

My maths is relatively weak, and I found the maths component trivially easy. Perhaps mathematics had a smaller part to play in society at this stage, because asking a university level student what a prime number is or how to do long division seems trivial.

Doing cube root by hand is more tricky though.

I'd characterize it as 'pointless tedium' and I'm glad our educational system is rid of it. It's easier to justify teaching Latin than that drudgery.

Of course if you're doing it by trial and error on paper it is pointless tedium. But I'm sure that the point of doing these exercises were not bore you to death, but to really make you understand arithmetic so you can do most given problems faster. If all you knew was how to multiply and divide numbers by hand, that problem would take you hours to solve!

A great example is the section 'lucky numbers' in Feynman's book:

http://lib.ru/ANEKDOTY/FEINMAN/feinman_engl.txt

True enough, except it's also along the lines of memorizing the works of Cicero or knowing all of the books of the Bible off by heart: It's useful at developing a skill that the correct tools render obsolete (cheap books in the case of the memory feats, computers in the case of the arithmetical ones). Similarly, knowing Latin and Greek had a purely practical motive as well back then: It marked you as a member of the social elite, defined as people who had enough leisure to study objectively useless things such as Latin and Greek. Memorizing paradigms wasn't something a farmer's son could be expected to do, after all.

I suppose my point, which I expressed poorly, is that it can be interesting to examine how technology impacts coursework.

> that problem would take you hours to solve

I don't know, two Newton iterations are enough:

  *GHCi> let croot f x = x - (x^3 - f) / (3*x^2) in take 5 . iterate (croot 0.0093) $ 0.2
  [0.2,0.21083333333333332,0.2102957483409451,0.2102943717551532,0.21029437174614204]

Guessing 0.2 as a starting point is obvious enough because 0.2^3 = 0.008.

Math transcends time and often language.

It also helps that the field of math has expanded and progressed a decent amount since the time of the exam, (i.e. what was cutting edge and difficult then is common knowledge now) while the fields of Latin and History haven't progressed so much as just gotten older.

Arty type here. I found the history/geography section way easier. But in saying that, I did get the feeling that a lot of the maths would have been trivial if I'd even just briefly studied it.

Probably. Coming from the same perspective, I agree.

I'd say some of it is pointlessly tedious, though, such as the one with manual division.

This is not the entrance exam for math majors, it's the entrance exam for everyone. The math is much more difficult than the entrance exams I took, though mine did offer sections on a broader set of topics, if you were familiar, to let you place out of courses.

Easy with a calculator yes, without one, not so much.

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