Anyone willing to take a stab at the high school math exam, Russian style?

[KrazyHorse]

The official solution onodera posted uses arithmetic sequences. I just saw that n was probably 5 and so k had to be 3, and a little bit of tweaking revealed that there probably weren't any other solutions.

It took me about 10 minutes. n is divisible by 5, but cannot be bigger than 10 and cannot be even.

[Hauldren Collider]

And I did, too. Haven't seen it since at least high school.

How in hell did you not run across arithmetic series when getting your finance degree? I don't even understand.

[Hauldren Collider]

Part of me wants to believe Alby is just playing dumb and trying to sound more stupid than he is.

[Al B. Sure!]

http://en.wikipedia.org/wiki/Arithmetic_sequence

I should clarify that they are perhaps using some other sequence-based argument. I just saw the a[n], a[n-1] etc. in the answer page (which I can't otherwise read) and assumed.

Still not understanding how they got from point A to point B...

True knowledge is measured by one's ability to teach. Perhaps you should explain.

[Hauldren Collider]

No, true knowledge is measured by how much of a dumbass someone isn't.

[Al B. Sure!]

How in hell did you not run across arithmetic series when getting your finance degree? I don't even understand.

You don't. Or maybe I know what an arithmetic series is but looking at that wikipedia article isn't ringing any bells. I have no idea what that article is talking about. This is kind of like with b etor when she asked about options and KH sent her a link to a wikipedia article and I said that's not going to do her any good. Those articles are not written well for someone with no base knowledge who is trying to learn it.

Before my freshman year of college, I took a placement test. I placed out of all required math courses. That's all I know. I never had the need to take any pure math courses in college.

I also minored in Economics. You definitely don't need math for a BA in Economics. More than one Econ professor commented on the dearth of mathematical knowledge among Econ majors. The classes (beyond the Intro level, obviously) were entirely composed of Finance and Econ majors and it was always evident that the Finance majors had more knowledge of math than the Economics ones. My course in Econometrics did not have a single Econ major in our class, in fact! So Economics, I guess, is even more of an embarrassment.

You just don't need this stuff. I rarely did anything more than algebra in finance and economics. If we needed any calculus, it was only for certain, well-spelled-out applications.

[Al B. Sure!]

No, true knowledge is measured by how much of a dumbass someone isn't.

Ditch this respect for arrogance. Your brother (and especially KH) are asses. Maybe KH is great at explaining things and he just has no inclination to do so on an internet forum but I have a suspicion he's like certain people who know a lot but can not lower their mind down to the level to be able to explain things to someone who knows nothing about the subject matter. Being able to teach is a skill that I'm pretty sure your brother and KH lacks. Their 'infinite genius' blinds them to the ability to see the subject matter from the perspective of the clueless and present that subject matter in a way the clueless can understand.

From my limited experience, Jaguar is a lot better at explaining things than your brother is.

[giblets]

Plus, Temple University might not be the cream of the crop.

[Al B. Sure!]

Econometrics and when we covered Black-Scholes in derivatives class were the most math-intensive courses I came across in college. Everything else was algebra.

[giblets]

You don't even know what exponents are, which is a surprise because I'd expect someone to encounter a Cobb-Douglas function at some point if they were taking economic courses in college.

[Al B. Sure!]

You don't even know what exponents are, which is a surprise because I'd expect someone to encounter a Cobb-Douglas function at some point if they were taking economic courses in college.

I know what exponents are. I don't know how to solve that problem in which you have a variable raised to a second variable + 1 power minus the factorial of the first variable.

And I WAS familiar with Cobb-Douglas functions and solving for exponents (all that log business) but I don't remember any of it now.

[Al B. Sure!]

I guess I did learn things for the test and then put the stuff out of my mind once the class was over. Fault me for that. Not like most people do any different

[Kuciwalker]

The point is that for #18 you don't "solve the equation" (at least, KH and I didn't). The equation gives you hints about restrictions on what values those variables can take, you take those hints and use them to derive further restrictions until you get the answer.

You are trying to do precisely what you were complaining about earlier, apply memorized techniques by rote.

[Al B. Sure!]

The point is that for #18 you don't "solve the equation" (at least, KH and I didn't). The equation gives you hints about restrictions on what values those variables can take, you take those hints and use them to derive further restrictions until you get the answer.

Explain, please. What are these hints? What are these further restrictions?

[giblets]

I know what exponents are.

Sorry, I mistook you for this guy:

What the **** is n superscript k+1? What does that mean?