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You are not logged in. #1 20111125 09:06:01
Useless parent puzzleHelp if you were numbering hotel room doors 12012 how many of each number (ie 19) would you need. Due in tomorrow pls answer ASAP. With workings! #2 20111125 09:17:45
Re: Useless parent puzzleHi Ozyhibby; 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. #3 20111125 09:24:57
Re: Useless parent puzzleIt's not for me. Trying to help my niece with homework. #4 20111125 09:29:43
Re: Useless parent puzzleHi; 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 20111125 19:36:27
Re: Useless parent puzzle
Signature line: I wish a had a more interesting signature line. #6 20111126 02:58:36
Re: Useless parent puzzleHi Ozyhibby; This corresponds to [1,2,3,4,5,6,7,8,9,0 ] meaning that there is one 5 needed and no zeros. To get the number needed from 10 to 99 we just multiply each number in vector A) by 10 and add 9 to each. Meaning 9 zeroes are necessary and 19 of every other number. To get the number needed from 100 to 999 we just multiply each number in B) by 10 and add 90 to each. So for instance we need 180 zeros. We are done with the numbers from 1 to 999. To get 1000  1999 is very simple. We know that there are 1000 ones used in th first digit and the other 3 digits are the same as above. We just have to add A,B and C. Remember the 1000 ones. We add the amount needed from 1 to 999 and from 1000 to 1999. Now we are only left with the numbers 2000,2001,2002,2003, ... 2011. We count them up by hand and get the vector: We add them to the subtotal: So the answer is the vector: We need 1604 ones and 513 zeros. 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. 