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farseer_dk
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PostPosted: 19 Apr 2010 06:41 PM Reply with quoteBack to top

Leaderboard
1) NotEmo = 4 points
2) JenJenJen, -Zephyr- = 3 points
3) Kakumei, takara-hoshi = 2 points (Kakumei successfully proved Washi's answer wrong in FBC #3)
4) strigger, Prilquob, VorpalBlade, Malentin = 1 point

Today's Questions

Today's questions are very difficult, so I am handing out extra points to people who get them. This time I have triple checked every question and have correct solutions to all of them.

Question 1 wrote:
3 points for answering this question by showing your logic. It is quite hard compared to past questions and requires at least BC grade 11 math.

Jason's investment horizon consists of three consecutive time periods. He spends a sum of money on investing at the beginning of each of three periods. Suppose that the amounts of the three investments may be different, which are denoted I1, I2, and I3, respectively. The net returns on his investment over the three periods are r1, r2, and r3, respectively.

Jason follows a buy-and-hold strategy. That is, for three investments, he does not do anything after purchases. He holds them all to the end of his investment horizon. Let a, b and c be three numbers such that -1 < a < b <c. Consider three possible cases:

1) r1 = a, r2 = b, r3 = c
2) r1 = d, r2 =d, r3= d where d is such that (1+d)^3 = (1+a)(1+b)(1+c)
3) r1 =c, r2 = b, r3 = a.

In which case does Jason have the highest total value of his investments at the end of the investment horizon? In which case does he have the lowest value? Make sure you offer logical proof along with your answer.


Question 2 wrote:
2 points for solving this and explaining your answer
"Human behavior cannot be fully understood without inquiring into nonphysical aspects of persons. As evidence of this, I submit the following: suppose that we had a complete scientific account of the physical aspects of some particular human action - every neurological, physiological and environmental event even involved. Even with all that we would obviously still not truly comprehend the action or know why it occurred."

What is the flaw in the above argument's reasoning?


Question 3 wrote:
A man who lives on the tenth floor takes the elevator down to the first floor every morning and goes to work. In the evening, when he comes back; on a rainy day, or if there are other people in the elevator, he goes to his floor directly. Otherwise, he goes to the seventh floor and walks up three flights of stairs to his apartment.

Can you explain why?

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Last edited by farseer_dk on 19 Apr 2010 09:16 PM; edited 3 times in total
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NotEmo
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PostPosted: 19 Apr 2010 06:43 PM Reply with quoteBack to top

#3...
hes not tall enough to reach the 10th floor button

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farseer_dk
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PostPosted: 19 Apr 2010 06:44 PM Reply with quoteBack to top

NotEmo wrote:
#3...
hes not tall enough to reach the 10th floor button

Correct. +1.

The easy one went way fast lol.

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VorpalBlade
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PostPosted: 19 Apr 2010 06:44 PM Reply with quoteBack to top

ill complete 3.

he uses the umbrella to poke the buttons he can't reach on rainy days.

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farseer_dk
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PostPosted: 19 Apr 2010 06:46 PM Reply with quoteBack to top

VorpalBlade wrote:
ill complete 3.

he uses the umbrella to poke the buttons he can't reach on rainy days.


or he can ask other people to press the button for him.

i think once people get that he's short the rest is kinda obvious.

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NotEmo
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PostPosted: 19 Apr 2010 06:46 PM Reply with quoteBack to top

#2...
they can't take into consider the random factor... of people being random

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farseer_dk
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PostPosted: 19 Apr 2010 06:47 PM Reply with quoteBack to top

NotEmo wrote:
#2...
they can't take into consider the random factor... of people being random

uhhh... no...

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Malentin
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PostPosted: 19 Apr 2010 06:53 PM Reply with quoteBack to top

On question 2:
Truth can never be known in science. Everything is an assumption, so yeah, we will never "truly" know anything.

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farseer_dk
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PostPosted: 19 Apr 2010 06:57 PM Reply with quoteBack to top

Malentin wrote:
On question 2:
Truth can never be known in science. Everything is an assumption, so yeah, we will never "truly" know anything.

No. There's a clear logical flaw in her argument.

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PostPosted: 19 Apr 2010 06:58 PM Reply with quoteBack to top

farseer_dk wrote:
Malentin wrote:
On question 2:
Truth can never be known in science. Everything is an assumption, so yeah, we will never "truly" know anything.

No. There's a clear logical flaw in her argument.

"some particular human action" seems to be the problem.. you can't truly comprehend anything with only partial information..

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PostPosted: 19 Apr 2010 07:12 PM Reply with quoteBack to top

question 2
The argument only shows that if you know the physical aspects, it's not enough understand the human behavior. It doesn't show that you must inquire nonphysical aspect of persons to understand, which is the statement in the beginning.

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farseer_dk
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PostPosted: 19 Apr 2010 07:15 PM Reply with quoteBack to top

For question 2, stop picking on the specifics of the statement and break it down into a generic logical argument. You will see that it has a flaw.

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Last edited by farseer_dk on 19 Apr 2010 07:35 PM; edited 2 times in total
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Yanslayer
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PostPosted: 19 Apr 2010 07:43 PM Reply with quoteBack to top

2 : Neurological is nonphysical o.o

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PostPosted: 19 Apr 2010 08:16 PM Reply with quoteBack to top

Yanslayer wrote:
2 : Neurological is nonphysical o.o


Neurological being the workings of the brain, like the electrical signals that are sent and stuff. aka physical

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PostPosted: 19 Apr 2010 09:03 PM Reply with quoteBack to top

#2

The flaw is that if you know of EVERY event involved, it's impossible to not know why it occurred because there is no possible reason that you don't already know. You can only "not know" something if there is something that you don't know. The statement assumes you know everything so it's impossible to not know why it occurred.

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