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Evaluate the combination:
15C5
A unique order or arrangement
nCr = | n! |
r!(n - r)! |
where n is the number of items
r is the unique arrangements.
15C5 2 | 15! |
5!(15 - 5)! |
n! = n * (n - 1) * (n - 2) * .... * 2 * 1
n! = 15!
15! = 15 x 14 x 13 x 12 x 11 x 10 x 9 x 8 x 7 x 6 x 5 x 4 x 3 x 2 x 1
15! = 1,307,674,368,000
(n - r)! = (15 - 5)!
(15 - 5)! = 10!
10! = 10 x 9 x 8 x 7 x 6 x 5 x 4 x 3 x 2 x 1
10! = 3,628,800
r! = 5!
5! = 5 x 4 x 3 x 2 x 1
5! = 120
15C5 = | 1,307,674,368,000 |
120 x 3,628,800 |
15C5 = | 1,307,674,368,000 |
435,456,000 |