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You are not logged in. #1 20060227 16:20:46
Permutations and CombinationsPC # 1 Character is who you are when no one is looking. #2 20060227 16:56:40
Re: Permutations and Combinationsfirst, I thank you ganesh for making this new themes. IPBLE: Increasing Performance By Lowering Expectations. #3 20060227 17:04:32
Re: Permutations and CombinationsSo if there are 2 ladies in the com, we have IPBLE: Increasing Performance By Lowering Expectations. #4 20060228 01:16:04
Re: Permutations and CombinationsTwo ladies must be in the committee. Character is who you are when no one is looking. #5 20060228 01:40:04
Re: Permutations and CombinationsOne simple muistake may change the answer badly: IPBLE: Increasing Performance By Lowering Expectations. #6 20060301 15:16:05
Re: Permutations and CombinationsPC # 2 Character is who you are when no one is looking. #7 20060301 16:51:59
Re: Permutations and CombinationsThey must be tigether so we have 3 subjects that must be arranged: IPBLE: Increasing Performance By Lowering Expectations. #8 20060301 18:46:51
Re: Permutations and CombinationsRead the question fully......and..... Character is who you are when no one is looking. #9 20060302 17:05:26
Re: Permutations and CombinationsPC # 3 Character is who you are when no one is looking. #10 20060303 03:39:11
Re: Permutations and CombinationsPC # 3 Why did the vector cross the road? It wanted to be normal. #11 20060303 15:33:52
Re: Permutations and CombinationsCharacter is who you are when no one is looking. #12 20060310 02:40:19
Re: Permutations and CombinationsPC # 4 Character is who you are when no one is looking. #13 20060312 02:49:57
Re: Permutations and CombinationsPC # 5 Character is who you are when no one is looking. #14 20060513 05:41:07
Re: Permutations and CombinationsGuess to PC#4 igloo myrtilles fourmis #15 20060513 14:47:12
Re: Permutations and CombinationsYou're correct, John! Well done Character is who you are when no one is looking. #16 20070917 21:22:02
Re: Permutations and Combinations
First, find ALL the combinations Since the formula is where r is (the number of positions)1 so now we see: combinations which don't accept 4's at the start and 54's. and we have: Done Last edited by landof+ (20070917 21:23:23) I shall be on leave until I say so... #17 20070918 09:09:37
Re: Permutations and CombinationsWoops I forgot some 57xyz, 58xyz, so add 12 to my answer sorry. Last edited by John E. Franklin (20070918 09:11:15) igloo myrtilles fourmis #18 20070918 21:24:43
Re: Permutations and CombinationsWhich is 90, same I suppose I shall be on leave until I say so... #19 20080723 15:07:15
Re: Permutations and Combinations
the answer should be !6 * !3 *!2 * !3 #20 20080821 17:58:10
Re: Permutations and CombinationsThere are 3 boys and 3 girls. In how many ways can they be arranged so that each boy has at least one girl by his side? #21 20080822 17:24:18
Re: Permutations and CombinationsThere are 10 boxes numbered 1, 2, 3, …10. Each box is to be filled up either with a black or a white ball in such a way that at least 1 box contains a black ball and the boxes containing black balls are consecutively numbered. The total number of ways in which this can be done is.. #22 20081012 23:09:37
Re: Permutations and Combinations
There are three ladies from which to choose the two slots designated for ladies. After those two slots are filled, there are eight unchosen members from which to randomly assign the remaining four committee seats. Why isn't the answer nCr(3,2)*nCr(8,4)=3*70=210? What am I missing? If I'm counting 70 possibilities twice, which possibilities am I double counting? Last edited by All_Is_Number (20081014 17:32:34) You can shear a sheep many times but skin him only once. #23 20081012 23:19:00
Re: Permutations and Combinations
You can shear a sheep many times but skin him only once. #24 20101020 07:04:54
Re: Permutations and CombinationsThis problem is old but... 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. 