Winamp & Shoutcast Forums Mathematical Logic [part 2]

25th March 2003, 21:48   #281
xzxzzx
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Quote:
 Originally posted by festerhead May I guess too?
Ding! Heheheh.

Freedom of speech is the basic freedom of humanity. When you've lost that, you've lost everything.
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 25th March 2003, 21:52 #282 anubis2003 Forum King     Join Date: Dec 2002 Location: middle of somewhere Posts: 5,564 That one was easy. I thought about that, but figured it would be deeper than that. [Over The Monkey] | [My DeviantArt] | [Seti] | [Atmo Digital Design Forums]
25th March 2003, 21:53   #283
zootm
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Quote:
 Originally posted by xzxzzx There are other factors, too. It's definately not perfectly 50/50.
unless you count the increased chance of her having a dominant gene that makes it more likely for her to have girls, it is, i believe. (having done something similar in probability)

25th March 2003, 22:00   #284
xzxzzx
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Quote:
 Originally posted by Orgone_Man Uhh... you could easily argue that BG and GB are the same when referring to this b/c wether or not the two siblings are a boy or a girl is not really "stackable" if you know what I mean. So, 50/50 would be correct if i'm not mistaken.
No you can't. These are the (roughly) equally probable situations:

GG GB BG BB

Just because GB and BG has the same number of girls and boys doesn't make them the same. Two girls is less likly than a boy and a girl, in either order. However, it is just as likly as a boy and a girl, in that order.

Freedom of speech is the basic freedom of humanity. When you've lost that, you've lost everything.
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 25th March 2003, 22:00 #285 dlinkwit27 has no CT(Forum King)     Join Date: Sep 2000 Posts: 13,235 lets play a game called "its a dumb ridlle, who realyl cares?"! ready?...go!
25th March 2003, 22:05   #286
xzxzzx
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Quote:
 Originally posted by anubis2003 That one was easy. I thought about that, but figured it would be deeper than that.
I was making a point of how stupid word-riddles are.

Freedom of speech is the basic freedom of humanity. When you've lost that, you've lost everything.
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 25th March 2003, 22:06 #287 anubis2003 Forum King     Join Date: Dec 2002 Location: middle of somewhere Posts: 5,564 A'ight. Point well made. [Over The Monkey] | [My DeviantArt] | [Seti] | [Atmo Digital Design Forums]
25th March 2003, 22:10   #288
xzxzzx
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Quote:
 Originally posted by zootm unless you count the increased chance of her having a dominant gene that makes it more likely for her to have girls, it is, i believe. (having done something similar in probability)
Well, there are other factors (identical twins, genetic tendancy, etc). But I suppose we should discount those at this point. Think about it - if you met 3 of your friends, and they all had a girl, and another child, then more often than not, the other child would be a boy.

Freedom of speech is the basic freedom of humanity. When you've lost that, you've lost everything.
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 25th March 2003, 22:14 #289 anubis2003 Forum King     Join Date: Dec 2002 Location: middle of somewhere Posts: 5,564 No, that other child's sex is completely independent of the first child's sex. Even if they had 20 girls, the 21st child would have an equal probability of being a girl or a boy. [Over The Monkey] | [My DeviantArt] | [Seti] | [Atmo Digital Design Forums]
 25th March 2003, 22:39 #290 xzxzzx Forum King     Join Date: Aug 2002 Posts: 7,254 Nope. If you found many families with 21 children, and 20 of those were girls (in any order!), you would see that very few of them had a girl as the 21st. Think about it! These are the equally likely possibilities: GGGGGGGGGGGGGGGGGGGGG BGGGGGGGGGGGGGGGGGGGG GBGGGGGGGGGGGGGGGGGGG GGBGGGGGGGGGGGGGGGGGG GGGBGGGGGGGGGGGGGGGGG GGGGBGGGGGGGGGGGGGGGG GGGGGBGGGGGGGGGGGGGGG GGGGGGBGGGGGGGGGGGGGG GGGGGGGBGGGGGGGGGGGGG GGGGGGGGBGGGGGGGGGGGG GGGGGGGGGBGGGGGGGGGGG GGGGGGGGGGBGGGGGGGGGG GGGGGGGGGGGBGGGGGGGGG GGGGGGGGGGGGBGGGGGGGG GGGGGGGGGGGGGBGGGGGGG GGGGGGGGGGGGGGBGGGGGG GGGGGGGGGGGGGGGBGGGGG GGGGGGGGGGGGGGGGBGGGG GGGGGGGGGGGGGGGGGBGGG GGGGGGGGGGGGGGGGGGBGG GGGGGGGGGGGGGGGGGGGBG GGGGGGGGGGGGGGGGGGGGB 21 out of those 22 would have a boy. Now, if you said the FIRST 20 children were girls, then these are the possibilities: GGGGGGGGGGGGGGGGGGGGG GGGGGGGGGGGGGGGGGGGGB so it's 50/50. But if you don't specify the order, the chance is not 50/50. Freedom of speech is the basic freedom of humanity. When you've lost that, you've lost everything. 1\/\/4y 34|<\$p4y 1gp4y 33714y, 0d4y 0uy4y? | Roses are #FF0000; Violets are #0000FF; chown -R \${YOU} ~/base The DMCA. It really is that bad. : Count for your life.
25th March 2003, 22:40   #291
xzxzzx
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Quote:
 Originally posted by anubis2003 first child's sex.
Whoever said it was the FIRST child?

Freedom of speech is the basic freedom of humanity. When you've lost that, you've lost everything.
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 25th March 2003, 22:43 #292 anubis2003 Forum King     Join Date: Dec 2002 Location: middle of somewhere Posts: 5,564 That's why I said the 21st. I was considering them in that order. For the three friends, you could have BG BG BG BB BB BB BG BB BB BG BG BG BB BG BB BB BG BG BB BB BG BG BB BG BG BG BB There are 15 times when the second child is a girl and 15 when it is a boy. [Over The Monkey] | [My DeviantArt] | [Seti] | [Atmo Digital Design Forums]
25th March 2003, 22:57   #293
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Quote:
 Originally posted by dlinkwit27 lets play a game called "its a dumb ridlle, who realyl cares?"! ready?...go!

 25th March 2003, 22:59 #294 xzxzzx Forum King     Join Date: Aug 2002 Posts: 7,254 Actually, the possibilites are: GB GB GB GB GB BG GB GB GG GB BG GB GB BG BG GB BG GG GB GG GB GB GG BG GB GG GG BG GB GB BG GB BG BG GB GG BG BG GB BG BG BG BG BG GG BG GG GB BG GG BG BG GG GG GG GB GB GG GB BG GG GB GG GG BG GB GG BG BG GG BG GG GG GG GB GG GG BG GG GG GG I never specified the order. A boy is twice as likely. Freedom of speech is the basic freedom of humanity. When you've lost that, you've lost everything. 1\/\/4y 34|<\$p4y 1gp4y 33714y, 0d4y 0uy4y? | Roses are #FF0000; Violets are #0000FF; chown -R \${YOU} ~/base The DMCA. It really is that bad. : Count for your life.
 25th March 2003, 23:02 #295 xzxzzx Forum King     Join Date: Aug 2002 Posts: 7,254 Let's play a game called "This is one of the few riddles that follow the name of this thread"! Ready? GO! Freedom of speech is the basic freedom of humanity. When you've lost that, you've lost everything. 1\/\/4y 34|<\$p4y 1gp4y 33714y, 0d4y 0uy4y? | Roses are #FF0000; Violets are #0000FF; chown -R \${YOU} ~/base The DMCA. It really is that bad. : Count for your life.
 26th March 2003, 02:24 #296 xzxzzx Forum King     Join Date: Aug 2002 Posts: 7,254 Somebody please prove me wrong, already. Freedom of speech is the basic freedom of humanity. When you've lost that, you've lost everything. 1\/\/4y 34|<\$p4y 1gp4y 33714y, 0d4y 0uy4y? | Roses are #FF0000; Violets are #0000FF; chown -R \${YOU} ~/base The DMCA. It really is that bad. : Count for your life.
 26th March 2003, 02:25 #297 dlinkwit27 has no CT(Forum King)     Join Date: Sep 2000 Posts: 13,235 your wrogn! oh. you said prove? fuq that.
26th March 2003, 05:56   #298
zootm
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Quote:
 Originally posted by xzxzzx Whoever said it was the FIRST child?
that's the problem - if you don't assume it's the first child, and have no more information, you either have to assume it's 50/50 (from the *rough* makeup of number of births of people in general) or just accept that there is not enough data. if you knew it was the first, your GG BG GB BB thing applies (otherwise the only options are GG BG BB, and it can't be BB, so it's 50/50 discounting alleviated probabilities).

26th March 2003, 06:51   #299
xzxzzx
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Quote:
 Originally posted by zootm that's the problem - if you don't assume it's the first child, and have no more information, you either have to assume it's 50/50 (from the *rough* makeup of number of births of people in general) or just accept that there is not enough data. if you knew it was the first, your GG BG GB BB thing applies (otherwise the only options are GG BG BB, and it can't be BB, so it's 50/50 discounting alleviated probabilities).
Um, no. If you know it is the first, then the only possibilities are GG and GB. If you don't know if it's the first or not, THEN the whole GG BG GB BB thing applies. It seems like you know this, but you're stating it the opposite way.

Again, someone please try and prove me wrong.

Freedom of speech is the basic freedom of humanity. When you've lost that, you've lost everything.
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 26th March 2003, 14:32 #300 zootm Forum King     Join Date: Jan 2002 Location: the nether reaches of bonnie scotland Posts: 13,375 if you don't know it's the first, that thing doesn't apply because without more data you can't make it order-dependant, so it's 50/50. if you do know it's the first child, then it's GG or GB (as you mention), so it's still 50/50. so unless the probabilities of one or the other is raised by outside forces, that's the most you can say for both, 50/50. sorry about some bits in that last post being wrong, it was 7am, and i'd just gotten back from work.
 26th March 2003, 18:22 #301 xzxzzx Forum King     Join Date: Aug 2002 Posts: 7,254 NO! GG is only half as likly as GB, if order is ignored. A random family is more likely to have a girl and a boy than two girls. Ok, this doesn't seem to be getting anywhere. I'll give you a 'hint' - all the logic I have presented so far is sound. However, it is missing something. What is missing? Freedom of speech is the basic freedom of humanity. When you've lost that, you've lost everything. 1\/\/4y 34|<\$p4y 1gp4y 33714y, 0d4y 0uy4y? | Roses are #FF0000; Violets are #0000FF; chown -R \${YOU} ~/base The DMCA. It really is that bad. : Count for your life.
 26th March 2003, 18:42 #302 FesterHead Alumni     Join Date: Sep 2001 Location: Maui, Hawaii Posts: 14,108 The father
 26th March 2003, 19:44 #303 xzxzzx Forum King     Join Date: Aug 2002 Posts: 7,254 The father is irrelevant. Freedom of speech is the basic freedom of humanity. When you've lost that, you've lost everything. 1\/\/4y 34|<\$p4y 1gp4y 33714y, 0d4y 0uy4y? | Roses are #FF0000; Violets are #0000FF; chown -R \${YOU} ~/base The DMCA. It really is that bad. : Count for your life.
 26th March 2003, 21:27 #304 anubis2003 Forum King     Join Date: Dec 2002 Location: middle of somewhere Posts: 5,564 Let's just go to the next riddle. This one is really getting irritating. [Over The Monkey] | [My DeviantArt] | [Seti] | [Atmo Digital Design Forums]
26th March 2003, 21:32   #305
xzxzzx
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Quote:
 Originally posted by anubis2003 This one is really getting irritating.
Excellent. I have stumped the board, apparently.

Freedom of speech is the basic freedom of humanity. When you've lost that, you've lost everything.
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 26th March 2003, 21:36 #306 anubis2003 Forum King     Join Date: Dec 2002 Location: middle of somewhere Posts: 5,564 No, you have asked a question that we don't like(at least I don't like it). I don't agree at all with what you are saying. [Over The Monkey] | [My DeviantArt] | [Seti] | [Atmo Digital Design Forums]
 26th March 2003, 21:43 #307 xzxzzx Forum King     Join Date: Aug 2002 Posts: 7,254 But how is it wrong? What do you disagree with? That's the difficult part. Actually, I can explain how what I am saying is "wrong" (well, misleading, anyway). I'll give zootm a chance first. This is a classic statistical puzzle. If I hadn't stumped the board, by the way, it would already be answered, wouldn't it? Freedom of speech is the basic freedom of humanity. When you've lost that, you've lost everything. 1\/\/4y 34|<\$p4y 1gp4y 33714y, 0d4y 0uy4y? | Roses are #FF0000; Violets are #0000FF; chown -R \${YOU} ~/base The DMCA. It really is that bad. : Count for your life.
 26th March 2003, 22:37 #308 FesterHead Alumni     Join Date: Sep 2001 Location: Maui, Hawaii Posts: 14,108 I was never any good at sadistics (mispeling intended).
 26th March 2003, 23:01 #309 anubis2003 Forum King     Join Date: Dec 2002 Location: middle of somewhere Posts: 5,564 Yes, I had AP Sadistics last semester, and I think that what you are saying is wrong, but it keeps on being twisted back and forth by what everyone is saying that I can't make a decision based on it. [Over The Monkey] | [My DeviantArt] | [Seti] | [Atmo Digital Design Forums]
26th March 2003, 23:56   #310
Rumata
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Quote:
 Originally posted by xzxzzx But how is it wrong? What do you disagree with? That's the difficult part. Actually, I can explain how what I am saying is "wrong" (well, misleading, anyway). I'll give zootm a chance first. This is a classic statistical puzzle. If I hadn't stumped the board, by the way, it would already be answered, wouldn't it?
This is so silly, i finally decided to register an account.

if we assume that
GG BG GB BB are all equally probable and you know that one child is a girl, you know that

probability of BB AND either BG or GB is zero. that leaves us with GG and (BG or GB).

A simpler explanation is you don't have to order children in the order of their birth. you might as well order them in the order of being introduced to you. then it's simpler to understand that BB and BG cannot be true. therefore it's either GG or GB.

-- Rumata

27th March 2003, 00:45   #311
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Quote:
 Originally posted by Rumata This is so silly, i finally decided to register an account. if we assume that GG BG GB BB are all equally probable and you know that one child is a girl, you know that probability of BB AND either BG or GB is zero. that leaves us with GG and (BG or GB). answer is: 50/50. A simpler explanation is you don't have to order children in the order of their birth. you might as well order them in the order of being introduced to you. then it's simpler to understand that BB and BG cannot be true. therefore it's either GG or GB. -- Rumata
thats what i meant when i said 50/50 o so many posts ago. really! (hehe)

 27th March 2003, 00:47 #312 anubis2003 Forum King     Join Date: Dec 2002 Location: middle of somewhere Posts: 5,564 That makes sense to me. Don't know if it's the answer or not, but it seems like it could be. The question has been 'changed' so many times that I am no longer sure what I am looking for. [Over The Monkey] | [My DeviantArt] | [Seti] | [Atmo Digital Design Forums]
 27th March 2003, 00:54 #313 Rumata Junior Member   Join Date: Mar 2003 Posts: 11 Here's an amusing math problem for you. In one barn, there is some number of chickens and some number of goats. It is known that there are 13 heads and 40 legs. Question: how many chickens and how many goats are there? Condition: The reasoning must be purely arithmetic. No algebra allowed.
 27th March 2003, 00:57 #314 dlinkwit27 has no CT(Forum King)     Join Date: Sep 2000 Posts: 13,235 well, i ahve the answer using algrebra, but i can't do that, so i'm fuqed!
 27th March 2003, 00:58 #315 anubis2003 Forum King     Join Date: Dec 2002 Location: middle of somewhere Posts: 5,564 Well, I know that there are 6 chickens and 7 goats, but I can't explain it without algebra. [Over The Monkey] | [My DeviantArt] | [Seti] | [Atmo Digital Design Forums]
 27th March 2003, 01:00 #316 ujay Forum King     Join Date: Jul 2001 Location: London Posts: 6,072 Welcome Rumata, *whisper* another one suckered in *whisper* The chance of any person being male or female is always 50/50 regardless. Gender is determined by chromosomes not family relationships and there are only ever two outcomes. So what has the rest of it all been about then UJ
 27th March 2003, 01:02 #317 anubis2003 Forum King     Join Date: Dec 2002 Location: middle of somewhere Posts: 5,564 That's what I've been saying, but I think they might be talking about something else. Anyways, there is a new question now. [Over The Monkey] | [My DeviantArt] | [Seti] | [Atmo Digital Design Forums]
27th March 2003, 01:10   #318
Rumata
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Quote:
 Originally posted by anubis2003 Well, I know that there are 6 chickens and 7 goats, but I can't explain it without algebra.
Therein lies the trick. How would you explain this to a 7-year old?

Thanks, ujay.

 27th March 2003, 01:12 #319 anubis2003 Forum King     Join Date: Dec 2002 Location: middle of somewhere Posts: 5,564 Well, I could say 6heads plus 7 heads equals 13 heads, and 12 legs plus 28 legs equals 40 legs. [Over The Monkey] | [My DeviantArt] | [Seti] | [Atmo Digital Design Forums]
 27th March 2003, 01:16 #320 Rumata Junior Member   Join Date: Mar 2003 Posts: 11 But how would you teach the 7-year old to actually solve the problem for any number of legs/heads.
 Winamp & Shoutcast Forums Mathematical Logic [part 2]