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skittles School Math Nerd


Number of posts: 40 Age: 14 Location: Lost Registration date: 2008-08-14
 | Subject: Easy Counting Wed Aug 13, 2008 5:50 pm | |
| Find the number of ways the letters from the word SUPERCALIFRAGILISTICEXPEALIDOCIOUS can be arranged, using all of the letters. |
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Urc Starting Member

Number of posts: 13 Age: 14 Location: IN UR MOM Registration date: 2008-08-13
 | Subject: Re: Easy Counting Wed Aug 13, 2008 5:59 pm | |
| | skittles wrote: | | Find the number of ways the letters from the word SUPER CALI FRAGI LISTI CEXPE ALIDO CIOUS can be arranged, using all of the letters. |
That is a very, very mean problem
I guess it'd be
34! ----- 2!*2!*2!*3!*2!*3!*3!*6!*2!* |
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skittles School Math Nerd


Number of posts: 40 Age: 14 Location: Lost Registration date: 2008-08-14
 | Subject: Re: Easy Counting Wed Aug 13, 2008 6:02 pm | |
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Urc Starting Member

Number of posts: 13 Age: 14 Location: IN UR MOM Registration date: 2008-08-13
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AIME15 Hardcore TMF user


Number of posts: 163 Age: 13 Location: Pleasanton, CA Registration date: 2008-08-13
 | Subject: Re: Easy Counting Wed Aug 13, 2008 7:40 pm | |
| | skittles wrote: | | Find the number of ways the letters from the word SUPERCALIFRAGILISTICEXPEALIDOCIOUS can be arranged, using all of the letters. |
I'm way way too lazy to count all the letters and all the duplicates but:
The general formula is: for n DIFFERENT letters, its n!
If k of them are the same, it's n!/k!
if r of them are the same, and k of another letter are the same, it's n!/r!k!
And so on. |
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skittles School Math Nerd


Number of posts: 40 Age: 14 Location: Lost Registration date: 2008-08-14
 | Subject: Re: Easy Counting Thu Aug 14, 2008 6:22 am | |
| Yes, AIME15 is correct. For this particular question, the answer is 34!/2!2!2!2!2!3!3!3!6! (I think, if I did my counting right)
Last edited by skittles on Thu Aug 14, 2008 8:11 am; edited 1 time in total |
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xoangieexo Starting Member

Number of posts: 7 Age: 14 Registration date: 2008-08-14
 | Subject: Re: Easy Counting Thu Aug 14, 2008 6:38 am | |
| hmm i got that too but i counted fast so... hmm... |
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Urc Starting Member

Number of posts: 13 Age: 14 Location: IN UR MOM Registration date: 2008-08-13
 | Subject: Re: Easy Counting Thu Aug 14, 2008 7:05 am | |
| | Urc wrote: | | skittles wrote: | | Find the number of ways the letters from the word SUPER CALI FRAGI LISTI CEXPE ALIDO CIOUS can be arranged, using all of the letters. |
That is a very, very mean problem
I guess it'd be
34! ----- 2!*2!*2!*3!*2!*3!*3!*6!*2!* |
I got 6! instead of 5!..idk |
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skittles School Math Nerd


Number of posts: 40 Age: 14 Location: Lost Registration date: 2008-08-14
 | Subject: Re: Easy Counting Thu Aug 14, 2008 8:11 am | |
| | Urc wrote: | | Urc wrote: | | skittles wrote: | | Find the number of ways the letters from the word SUPER CALI FRAGI LISTI CEXPE ALIDO CIOUS can be arranged, using all of the letters. |
That is a very, very mean problem
I guess it'd be
34! ----- 2!*2!*2!*3!*2!*3!*3!*6!*2!* |
I got 6! instead of 5!..idk |
Oops, sorry, it is 6. |
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AIME15 Hardcore TMF user


Number of posts: 163 Age: 13 Location: Pleasanton, CA Registration date: 2008-08-13
 | Subject: Re: Easy Counting Thu Aug 14, 2008 11:17 am | |
| On a homework or competition, this would DEFINITELY not come up. Maybe, like find the number of permutations in the word HAPPINESS and TELEPHONE, but not something that has so much room to make a silly error. |
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skittles School Math Nerd


Number of posts: 40 Age: 14 Location: Lost Registration date: 2008-08-14
 | Subject: Re: Easy Counting Thu Aug 14, 2008 1:56 pm | |
| Haha, I just wanted to be mean. But as long as you know the method, it doesn't really matter. |
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Urc Starting Member

Number of posts: 13 Age: 14 Location: IN UR MOM Registration date: 2008-08-13
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