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# propsguy

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2. ## One Girl - One Boy

"One of them is a girl" means the same exact thing as "One of which is a girl"! You're saying that adding "at least" to "One of them is a girl" changes the meaning? It doesn't! Did you think that "One of them is a girl" didn't mean at least one? Did you think it meant both? Oh really? So which one did the OP assign, the first or the second? The answer is 'neither'. "One of them" means either one of them. Not the first and not the second. Yup! Ok guys, I was willing to let it go, but now I've been forced to reach into my bag of tricks and open up a can of logical whup-a** on you all. "One of them is a girl. What is the probability the other kid is also a girl?" "One of them." "The other kid." and again, "One of them." "The other kid." I'm not saying the OP assigned one of the children to be a girl. The question itself assigns one of them. Seems clear to me: There is "one", and there is the "other." We are asked about the probability of "The other kid." I don't care if it's the first or the second born. I don't care how you look at it: "One of them is a girl." As soon as you ask about "the other" you've made that "other" the subject of the probability. And the probability of "the other one" being a girl is 1/2. Nuff said.
3. ## socks

Ok, lets look at it this way (for clarity am stating the whole problem again..) A drawer has 5 black and 5 white socks. Your task is to pick a black pair, HOWEVER on removing a sock you are supposed to put it back if its not black. What is the probability of having a black pair in the 5th draw, 10th draw, 50th draw... Solution approach for a black pair on 2nd draw... To get a black pair on the 2nd draw, both the 1st draw and 2nd draw must be black. P(getting a black sock on 1st draw) = 1/2 P(getting a black sock on 2nd draw) = 4/9 (Since 1st sock was black it is not replaced leaving 4 black socks of total 9) So, the probability of getting a black pair on 2nd draw is 1/2 * 4/9 = 2/9. Similarly for getting a black pair on 3rd draw: 1) One of the 1st 2 picks have to be black - probability of either 1st OR 2nd resulting in black sock AND 2) 3rd draw must be black.. so y'all get the idea, try to figure a general formula.. And, since it is a probability question, the answer will have to be between 0 and 1 (both inclusive). That's about what I did to get my answer above. 1:4.5 could have read 2/9. The probablility is once in wvery 4.5 draws.

5. ## socks

By Jove, I think I've got it, though Mdsl seems to have posted a response too. Before I read his, I'll submit mine.... The chances of getting a black pair "in" any of the mentioned draws is 1:4.5
6. ## A Riddle

hmmmm. maybe "what is (at my) computer keyboard"
7. ## Lost Time

I would guess it has something to so with him starting in, say, Hawaii or Alaska, and flying at a precise speed before landing in specific locations. Maybe the earth's rotation affecting his southward bearing? Or, Maybe it is just too hard.
8. ## The liar, the truth teller....and the random answerer

Holy crap is that good Writersblock! I'm looking for the "Bow-down" key on my computer.
9. ## A Riddle

what is (at my) computer??
10. ## One Girl - One Boy

I think it might be a not-so-sneaky way of saying "I read too much into the puzzle" I thought the puzzle was working with an additional, or deeper twist: like: "you have two coins in your pocket totalling 30 cents in value. One of them is not a quarter" That classic works as a puzzle, specifically because it does assign. So when I looked over the words "one of them" I took that to be a crucial part of the puzzle. I've been wrong before and I'll be wrong again Dammit. Sneaky?... not so much.
11. ## socks

7. Your task is to pick a black pair, on removing a sock you are supposed to put it back if its not black. What is the probability of having a black pair in the 5th draw, 10th draw, 50th draw Oww, my head hurts. A question for you: If the first sock happens to be a white one, and you put it back does the next sock picked count as the 2nd draw, or the 1st? I'm assuming that you mean it to count as the 2nd. And so on....

13. ## Desert Treasure!

Like a mom's trick with two children and the last piece of cake: one gets to cut, the other gets to choose.
14. ## me and Alexander Hamilton

Hamilton was Burr's second in the duel. They were on the same 'side'?
15. ## just a riddle

An umbrella?
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