bonanova
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Everything posted by bonanova
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Four statements ... four responses: The math does not matter, if you start with a false premise. The first baby's sex is not given. Possibly because you are not answering the question in the OP. You say.
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Gazza, If you perceive silence from the "1/3 crowd", you might consider the possibility that it's not because you have persuaded them - they may have just concluded that you're impervious to logic. It's more convincing to post proofs than it is to hint, for example, that it's not about logic, anyway, but about semantics. You might even try to say what that means. For starters ... your statement in red above. Can you give a counter-example? Show a case where both "one" and "the other" of two children are female, but it's not the case that they both are girls.
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That's your mistake. There are three cases, each with a probability of 1/3. The sibling is an older boy The sibling is a younger boy The sibling is an older or younger girl. [in the gg case, it doesn't matter which child "a girl" refers to - there is only one gg case - it may not be double counted.] The conditional chances that the sibling is a girl, respectively, in the three cases are0 0 1 So the probability of the other child being a girl is 0*1/3 + 0*1/3 + 1*1/3 = 1/3.
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No, it's not. The question is not that trivial. You are only told that the two children are not both boys. "One of the children is a girl" does not make the first child a girl.
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I think we all agree that the question My first child is a girl, what is the probability my second child is a girl is lame. Please read the OP and some of the other posts in this thread. Then use your 1st grade math to see that the question actually being asked is not lame.
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Pardon the sarcasm. I just found it really improbable that you believe girl-girl and mixed gender families occur with equal likelihood. And that certainly follows from your answer: that removing the boy-boy case leaves the girl-girl case with 50% likelihood. Care to comment [specifically] on that point?
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You're welcome. So what you claim is that when 2-boy families are eliminated, half of the remaining families have 2 girls, and the other half are mixed-gender families. Given that p[bB]=0. then p[GG] = p[bG or GB] = 1/2. Do you really believe that 2-girl families and mixed-gender families occur with the same probability? We know that in the general population p[bB] = p[GG] so that means when p[bB] not = 0, p[bB] = p[GG] = p[mixed] = 1/3. Thanks for news ! Most of us thought p[bB]=p[GG]= 1/4 and p[mixed] = 1/2. Now we know better. Wait. We know that she is older or younger, so 2, 3 and 4 all apply. p[GG] = p[older or younger]*p[GG] = 1 * 1/3 = 1/3. Whew! You had us believing you were serious for a moment.
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You got it. And you're right, only 6 encodings manages the task.
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http://brainden.com/forum/uploads/emoticons/default_wink.png' alt=';)'> Looks like a win! And, yes, a larger deck can be accommodated. I know how much larger, by another source
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Yeah ... CA bends quite a bit.
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It might have been too convoluted for my fading brain ... I'll go back and check. ---- minutes pass ---- OK, I'm back I guess that part of your method is not clear to me.
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Yes, you did. But read the second spoiler above and see that no other signals are involved.
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Yes, but what does it take to completely paint that rectangle? e.g., starting with the four corners encompasses, but does not paint, the entire square. Shall I give a clue?
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Clearly, when they took globes out of classrooms, something was lost. Kudos to HoustonHokie who not only was the first to be correct, but the first to post! WESTICLES covered his bet by naming two states. <_< One out of two ain't bad. Finally, Blonde Girl jokingly got it right, claiming she had no idea! Even a blind squirrel finds an acorn once in a while. Honorable Mention goes to yellowsubmarine, who couldn't resist the urge to Google Earth the thing, but had the restraint not to post the answer.
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Hi brainz, You showed that 3 is "a correct answer". You did not show it is "the correct answer". The OP asks: "couldnt he have 2 cars and none of them be a honda toyota or ford?" In other words, if there can be more than one correct answer, is 2 one of them? Try to show that 3 is the only possible answer.
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You're in the USA and want to travel to Africa by the shortest distance. What US state should you leave from?
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Is there a solution if Amber returns the cards to Waldo all face down?
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holatravis, puzzlegirl and lemonymelon [with map assistance] have it. Nice job.
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Cherry Lane has it ... Nice.
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What is the largest US city east of Reno, NV and west of Denver, CO? Do you really need to look at a map???
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Two friends, Jim and John, were texting each other one night. One was in an East Coast [uSA] state, the other in a West Coast state. Just to clarify, the two states had borders on the Atlantic and Pacific Oceans, respectively. "What time is it where you are?" Jim typed. "The same time it is where you are!" John replied. Could John have been telling the truth?
