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Posted: 2/23/2002 4:04:37 AM EDT
I had a math teacher tell me that from the letters and numbers, abc123; There are over 17 million combinations that can be used.
She asked me how they came up with that figure.
Does anyone have the answer?
signed
Einstein. ;)



first of all, your teacher's wrong (assuming she's not counting "aaaaaa" etc. as a combination. (Even then, I dont think she'd be right.) The actual number is 720 different combinations. The way to figure it out is by doing a permutation of 6 on 6. What this is, for those who don't know, is: suppose you had those 6 numbers in a hat and drew one after the other out until youve drawn all 6. In this case, the order matters, which means "cba321", "b2c3a1," "cab132" etc. are all completely different outcomes. To count this, you do a permutation of 6 out of 6 (meaning: of 6 choices in the "hat", you draw 6 at random). The math for this is 6!/(66)!, or 6!/0!, or simply 720. Hope it helps...I think Im right, I may be missing some important statistical principle, but as far as I know this is the way.



I think your teacher didn't explain it quite well enough. I think what you're after is not a combination or permutation, but something akin to the total number of license plates possible given 3 letters followed by 3 digits. If this is what she means, the answer is
26x26x26x10x10x10=17,576,000
AZ=26
09=10


"Okay, but I'm not good at details, or the big picture. I also show up late, and drunk. I've got a good feeling about this."
 Homer Simpson 
abc,acb,bca,bac,cab,cba
+
123,132,231,213,312,321
combine any set together and do the same thing.
abc123,abc132,abc231,etc.etc.
#c*12*
aw hell its been too long since i was in math class to know the exact formula.
assuming the characters could only be used once in any equasion, its a probabilities game
randomely selected, there are 6 probabilities for c(character)1, then ehatever C is in position 1 can't be in any other position, so there are only 5 C's to choose from in the second choice. etc,etc
6*5*4*3*2*1=720 for each C1
multiplie that thimes the nomber of possable C1's
720*6=4320
the # of possable C2's is equal to 5*4*3*2*1=120 for each C2 multiplie for each possable C2
120*5=600
keep doing this and you come up with
4*3*2*1=24*4=96
3*2*1=6*3=18
2*1=1*2=2
1=1*1=1
add 1+2+18+96+600+4320=5037 permutations. this is for ONE possable C1
so the possabilities of any set of # starting with A = 1 in 5037
multiplie this # times the # of possable C1's and you come up with 5037*6=30222 so the possabilitie of any permutation begining with A3 (for example) is 1 in 30222
multiplie this # times the # of possable C2's and you come up with 30222*5=151110
keep doing this and this is what you get.
151110*4=604440*3=1813320*2=3626640*1
or maby its *6#of previouse C's
anyway you get the idea that it is a long mathematical equasion.. that you have to be einstien to really understand..



Originally Posted By Berserker:
first of all, your teacher's wrong (assuming she's not counting "aaaaaa" etc. as a combination. (Even then, I dont think she'd be right.) The actual number is 720 different combinations. The way to figure it out is by doing a permutation of 6 on 6. What this is, for those who don't know, is: suppose you had those 6 numbers in a hat and drew one after the other out until youve drawn all 6. In this case, the order matters, which means "cba321", "b2c3a1," "cab132" etc. are all completely different outcomes. To count this, you do a permutation of 6 out of 6 (meaning: of 6 choices in the "hat", you draw 6 at random). The math for this is 6!/(66)!, or 6!/0!, or simply 720. Hope it helps...I think Im right, I may be missing some important statistical principle, but as far as I know this is the way. View Quote 


Originally Posted By mattja:
I think your teacher didn't explain it quite well enough. I think what you're after is not a combination or permutation, but something akin to the total number of license plates possible given 3 letters followed by 3 digits. If this is what she means, the answer is
26x26x26x10x10x10=17,576,000
AZ=26
09=10
View Quote 


Originally Posted By the_survivalist:
Originally Posted By mattja:
I think your teacher didn't explain it quite well enough. I think what you're after is not a combination or permutation, but something akin to the total number of license plates possible given 3 letters followed by 3 digits. If this is what she means, the answer is
26x26x26x10x10x10=17,576,000
AZ=26
09=10
View Quote View Quote 

"Okay, but I'm not good at details, or the big picture. I also show up late, and drunk. I've got a good feeling about this."
 Homer Simpson 
i am begining to have nightmares of my school (indoctrination camp) days, i will stop looking in this thread now.



Now I have a headache.
Thanks.
Jon "Low Wattage" Sherman


"There are a great number of people who have guns that shouldn't have them. Or cars. Or children. Or oxygen...."
Pat _Rogers 
Mattja is right if the order is 3 letters followed by 3 numbers. If these can be in any order...then the number goes way up from there. License plates are figured this way because the order of the letters and numbers is constant.



If the letter A,B,C are travelling west bound on a train at 50 mph. And the numbers 1,2,3 are travelling east bound at 72 mph. How long will it take janet reno to burn your house down?


The purpose of fighting is to win. There is no possible victory in
defense. The sword is more important than the shield, and skill is more important than either. The final weapon is the brain. All else is supplemental. 
Originally Posted By The_Beer_Slayer:
If the letter A,B,C are travelling west bound on a train at 50 mph. And the numbers 1,2,3 are travelling east bound at 72 mph. How long will it take janet reno to burn your house down? View Quote 

Women and cats will do as they please, and men and dogs should
relax and get used to the idea. Robert A. Heinlein Drugs kicked in now, need sleep, radiation tastes funny at 7 am every day... a bit like victory.  Ginger 
Obviously you've missed the whole point of this math lesson:
How did you FEEL about the question?
Knowing that there is no "right" or "wrong", only different shades of gray, what is YOUR answer?
Now paint a picture of your thoughts of what your teacher told you.
Did this math lesson trigger any latent homosexual thoughts that our team of school counselors can help you uncover?
THESE are the real lessons to be learned from your math problem.


I am not the means to any end others may wish to accomplish. I am not a tool for their use. I do not surrender my treasures to be flung to the winds as alms for the poor.
~ From "Anthem" 
Originally Posted By The_Beer_Slayer:
If the letter A,B,C are travelling west bound on a train at 50 mph. And the numbers 1,2,3 are travelling east bound at 72 mph. How long will it take janet reno to burn your house down? View Quote 


Originally Posted By The_Macallan:
Obviously you've missed the whole point of this math lesson:
How did you FEEL about the question?
Knowing that there is no "right" or "wrong", only different shades of gray, what is YOUR answer?
Now paint a picture of your thoughts of what your teacher told you.
Did this math lesson trigger any latent homosexual thoughts that our team of school counselors can help you uncover?
THESE are the real lessons to be learned from your math problem.
View Quote 


WTH was all that crap? There are only a couple kinds of math out there that are worth a damn.... here are two of them! [:D]
Beer math is: 2 beers times 37 men = 49 cases.
Body count math is: 2 guerillas plus one portable, plus 2 pigs = 37 enemy killed in action.
.


MIA: M/SGT James W. Holt USSF 2768 SVN
"It is not the function of the government to keep the citizen from falling into error; it is the function of the citizen to keep the government from falling into error."  Justice Robert H. Pa 
Originally Posted By Guzzler:
Oh man!!! Don't start with that shit. This philosophy of teaching that there are no wrong answers started my senior year of high school. In a MATH class of all places.
View Quote 


Originally Posted By Hoplophile:
What's that quote? Something like "You can argue religion and philosphpy all you want, but if you're building rifles or space ships then 2 plus 2 had better equal 4" View Quote 


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