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You are not logged in. #1 20121218 02:35:52
boys and girls6 boys and 6 girls are sitting in a row . Then the no. of ways that boys and girls sits alternatively #2 20121218 02:49:35
Re: boys and girlsHi; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #4 20121218 03:06:22
Re: boys and girlsArrange the girls first in a line; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #5 20121218 03:11:10
Re: boys and girls
Your mistake is in
You can't do that as that allows for possibilities in which there's a girl at both ends, which you don't want. The possibilities are either X_X_X_X_X_X_ or _X_X_X_X_X_X Each set has ways; hence there are ways altogether. #7 20121218 11:07:45
Re: boys and girls
Not at the same time! In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #8 20121218 11:10:53
Re: boys and girlsWell, maybe the girls at the ends are in a superposition and our observation force the situation to enter one of the two possible states. The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #9 20121218 11:14:42
Re: boys and girlsPoint is, sometimes it is a guy and sometimes it is not. Depending on what slot the last guy goes into. In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #10 20121218 11:15:45
Re: boys and girlsI was just kidding! The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #11 20121218 11:19:42
Re: boys and girlsHmmmm. I know that. I know that you kid but you do not joke. In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #12 20121218 11:30:56
Re: boys and girls
Exactly. Jacks's method allows girls to be at boths ends at the same tiem – that was where his proof went wrong. 