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August 17th, 2011


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07:05 pm - Because MATH, that's why.
You roll two fair 6-sided dice.

One of them is a 6.

What are the odds that the other is also a six?

Poll #1770498 Guess the fraction!

What are the odds that the other die is also a six?

1/6
131(78.4%)
1/2
0(0.0%)
5/36
2(1.2%)
2/6
0(0.0%)
17/36
1(0.6%)
16/36
0(0.0%)
6/256
2(1.2%)
1/36
13(7.8%)
Something else, that I will explain in a comment
18(10.8%)

(104 comments | Leave a comment)

Comments:


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From:tsunami_ryuu
Date:August 17th, 2011 11:12 pm (UTC)
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Ahhh, tricksy question. I answered incorrectly because I didn't think that one through. It's all in the wording.
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From:theweaselking
Date:August 17th, 2011 11:26 pm (UTC)
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You can re-answer by clicking the poll number and clicking "Fill Out Poll"
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From:theweaselking
Date:August 17th, 2011 11:25 pm (UTC)
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Seriously, people?
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From:chaosrah
Date:August 17th, 2011 11:30 pm (UTC)
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If you already rolled one die, then the second die is independent of the first. 1/6, right? I mean, if you rolled two die and said what are the chances they are both 6s, that's 6x6, 1/36. I know I'm not good at math, but I remember these tricky things in school.. If I'm wrong, I need an explanation.
[User Picture]
From:dianavilliers
Date:August 17th, 2011 11:37 pm (UTC)
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1/11.
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From:theweaselking
Date:August 17th, 2011 11:43 pm (UTC)
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How do you reach this conclusion?
From:silmaril
Date:August 18th, 2011 12:59 am (UTC)
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1/11.

(This is how tired I am: I had to actually write out the complete set, delete everything that didn't have a six in it, and count. I was left with {(6,1),(6,2),(6,3),(6,4),(6,5),(1,6),(2,6),(3,6),(4,6),(5,6),(6,6)}, which I rewrote here and recounted just to make sure my count was right. I think if you were to pull out the flaying knives now I might be able to do the formal derivation, but not otherwise. Tiiiiiiired.)
From:silmaril
Date:August 18th, 2011 01:01 am (UTC)
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(Also, I completely approve of both your choice of title for the post, and now that I have skimmed up, dianavilliers' choice of method of illustration.)

Edited at 2011-08-18 01:02 am (UTC)
[User Picture]
From:a1057soul
Date:August 18th, 2011 01:23 am (UTC)
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depending on how you read the question... there are 11/36 possible combinations where a 6 is present: 1-5,6 and 6,1-6.

The question asks if one of the die is a 6 and what is the probability that the other is ALSO a six... this to me indicates BOTH sixes, which has a probability of 1/36 based on each having 6 outcomes on two dies... assuming of course 'fair sided' means numbering from 1-6 (this isn't stated).

The probability of rolling a 2nd six after identifying the first is 1/6, but the probability of rolling 2 sixes is 1/36.

But then I generally do my math like this.

:o.
Dan
[User Picture]
From:theweaselking
Date:August 18th, 2011 01:36 am (UTC)
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No, the question states that one of the two is a 6, without ever saying which.

And yes, I know Durkon. He's several close personal friends.
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From:crazy_alexy
Date:August 18th, 2011 01:34 am (UTC)
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This shit is why I hate math. -.-
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From:theweaselking
Date:August 18th, 2011 01:47 am (UTC)
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There's only 36 possible answers! brute-force exhaust it!
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From:ipslore
Date:August 18th, 2011 02:01 am (UTC)
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Okay, there's four possibilities:
1) *The one that's a six is a six, and the other one is a six
2) *The one that's a six is a six, and the other one is not a six
3) *The one that's a six is not a six, and the other one is a six
4) *The one that's a six is not a six, and the other one is not a six.

Clearly, we can eliminate 3) and 4). That leaves us with a 1 in 6 probability that the die other than the die that's a six is also a six.

(alternate, smart-ass answer: the odds are 0, because 'one of them' means 'exactly one of them'.)
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From:theweaselking
Date:August 18th, 2011 02:04 am (UTC)
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No, and no.
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From:kafziel
Date:August 18th, 2011 02:40 am (UTC)
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Without reading other comments: is it 1/11?
(Deleted comment)
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From:dscotton
Date:August 18th, 2011 03:20 am (UTC)
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I got 1/11. 11/36 die combinations include a six. 1 of those consists of two sixes.
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From:krinndnz
Date:August 18th, 2011 03:45 am (UTC)
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Yes, questions are harder to answer when they're worded badly. Every time you post this (e.g. the raptors) I think you're an asshole.
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From:pappy_legba
Date:August 18th, 2011 05:43 am (UTC)
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Livejournaler confuses poor wording for cleverness, film at 11.
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From:ciphergoth
Date:August 18th, 2011 08:08 am (UTC)
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From:ali_in_london
Date:August 18th, 2011 06:22 am (UTC)
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[x] Some initial answer, but then reading the comments convinced me I was wrong.
From:tempter
Date:August 18th, 2011 06:37 am (UTC)
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I'm curious what you think the answer is.
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From:theweaselking
Date:August 18th, 2011 12:37 pm (UTC)
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It's 1/11.

You have rolled two dice. One of them is a six, meaning you have 11 possible combinations. Of those 11, one has two sixes.
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From:fridgepunk
Date:August 18th, 2011 03:56 pm (UTC)
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1/6 because the die that came up six is loaded and always comes up 6.

Problem?
[User Picture]
From:theweaselking
Date:August 18th, 2011 03:59 pm (UTC)
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This is like the "100%, because I am actually Agent Michael Scarn of the FBI, and I have a gun!", right?

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