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        riddles >> hard >> Think You're Good?
        
(Message started by: Jimmy Hansen on Sep 30^th, 2002, 8:51pm)

Title: Think You're Good?
Post by Jimmy Hansen on Sep 30^th, 2002, 8:51pm

http://www.highiqsociety.org/common/smartest.htm

Title: Re: Think You're Good?
Post by Garzahd on Oct 11^th, 2002, 8:30pm

This looked really interesting, and I've been working on it for a good hour or two now, but I've already found 2 flaws in the exam already.

One is in question 10, where the question on the printable version is different than the normal version (check the 3rd red image)

The other is on question 6, though it's possible my so-called flaw may actually be the answer, so I'll hide it...

The letter Y is never used in the first 25 names, so the problem is unsolvable.

Title: Re: Think You're Good?
Post by Eric Yeh on Oct 12^th, 2002, 4:32pm

Ye, I also had a few interpretation questions. For one thing, I believe #25 is strongly underspecified -- anyone agree?

Best,
Eric

Title: Re: Think You're Good?
Post by Garzahd on Oct 13^th, 2002, 7:33pm

Agreed. I could come up with an answer to 25 only after assuming:
(a) everyone meets someone
(b) there's some unspecified death rate that keeps the population constant
(c) reproduction is asexual

A lot of the problems are cool, but I don't like that many of them (4, 6, 18, 21, 22, and possibly 2, 9, 11, and 17) seem best solved by brute force. Having a linear-equation solver and C compiler on hand doesn't make me a more intelligent person.

Side note: On 22, I've got a solution that makes sense for all except the right column and the bottom row, and I suspect it might be a bug in their diagram. I'll let people figure it the puzzle on their own, but it seems to me that ..... the bottom row should be 88 and the right column should be 97.

Title: Re: Think You're Good?
Post by Eric Yeh on Oct 14^th, 2002, 7:02am

Exactly. Oh, and that all offspring develop the same breeding characteristic, which is not otherwise clear. I find (a) exceptionally unrealistic, and (c) particularly odd (the wording should have been set up differently if that was intended, since of the relatively few classes of asexually reproducing organisms I know, none of them are advanced enough to exhibit fighting instinct and territorialism). (b), while potentially realistic, renders the number 4000 completely theoretically irrelevant (they should just ask for a fraction), but potentially small enough that you can run into problems of discreteness. Ok I guess its unlikely, but I haven't worked out the details.

Best,
Eric

Title: Re: Think You're Good?
Post by Chronos on Oct 14^th, 2002, 6:37pm

On question 4, I can do it with 1 ball in the final pyramid. That's 0 in one original pyramid, and 1 in the other one ;) . But then, I can also have 0 in each of the first two, contradicting the problem's statement that 20 total is the minimum for identical pyramids.

On problem 6, I get the impression that each letter is to be associated with a different number in the set [1,26]. Even so, though, you still can't assign the odd value to the missing letter, because none of the names contains a Q, either. So there are at least 2 letters left over.

Question 12 asks about black circles, but the diagram shows red circles.

Question 21, in addition to being brute-force, is also underspecified. For any valid solution, you can always scale the whole thing by any integer to produce another valid solution. They probably should have asked for the smallest possible size for the square.

Title: Re: Think You're Good?
Post by Garzahd on Oct 15^th, 2002, 10:32am

I finally managed to get ahold of someone's ear on their side.

On 10, the non-printable version is the correct diagram (Which is good, because my answer assumes that.)

On 6, this is literally the response I received:

Quote:

As for #6, it can be solved without the Y.
In fact, the missing Y is what makes it such an elegant, difficult question.

To which my first instinct is "yeah, right" ... but I'll at least give it another look. I'll also write back with the discrepancies and underspecifications in the other questions.

Title: Re: Think You're Good?
Post by Garzahd on Oct 17^th, 2002, 9:25am

Heard back from them again; they'll "look into fixing" the following:

nonzero specification in #4
black/red color nitpick in #11
scaling for infinite solutions to #21
my issue with 22 (maybe, unless my solution is actually wrong)
massive underspecification on #25