Question 507701: how many ways are there to choose 3 separate officeholder positions (pres,vp etc) from a group of 12 people?
at first i tried 12*11*10=1320
i tried this formula 12!/3!(12-3)!= 220
But then i was told it was just 12!
just want a conformation, thank you ahead of time
Answer by jim_thompson5910(35256)   (Show Source):
You can put this solution on YOUR website! Since order matters, you'll use the permutation formula
P(n,r) = n!/(n-r)!
In this case, n = 12 and r = 3
P(n,r) = n!/(n-r)!
P(12,3) = (12!)/((12-3)!)
P(12,3) = (12!)/(9!)
P(12,3) = (12*11*10*9!)/(9!)
P(12,3) = 12*11*10
P(12,3) = 1320
So there are 1320 different ways to choose 3 separate officeholder positions.
Let me know if you need more help or if you need me to explain a step in more detail.
Feel free to email me at jim_thompson5910@hotmail.com
or you can visit my website here: http://www.freewebs.com/jimthompson5910/home.html
Thanks,
Jim
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