SOLUTION: An election ballot asks voters to select 6 city commissioners from a group of 12 candidates. In how many ways can this be done. Use the formula nCr to solve. I am stuck please he

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Question 320930: An election ballot asks voters to select 6 city commissioners from a group of 12 candidates. In how many ways can this be done.
Use the formula nCr to solve.
I am stuck please help
Answer by nyc_function(2741) About Me  (Show Source):
You can put this solution on YOUR website!
Let n = total of city commissioners
Let r = how many candidate are taken from the total
This is a combination question from probability math.
The formula you need is given by: nCr = n!/[(n - r)! * r!]
The exclamation point (!) means factorial.
What is a factorial anyway?
A factorial is the product of all the positive integers from 1 to a given number.
For example, 6 factorial, written 6!, means 6 x 5 x 4 x 3 x 2 x 1 = 720.
What would 4! be? It is 4 x 3 x 2 x 1 = 24.
Understand?
============================================
Back to your question.
Let n = 12
Let r = 6
Replace every n! with 12 and every r! with 6 and then do the math.
nCr = 12!/[(12 - 6)!*6!]
nCr = 479001600/(720)(720)
nCr = 479001600/518400
nCr = 924
There are 924 ways or combinations to select 6 city commissioners from a group of 12 candidates.