17 Combinations of 3

17 Combinations of 3

Evaluate the combination:

17C3

Combination Definition:

A unique order or arrangement

Combination Formula:
nCr  =  n!
  r!(n - r)!

where n is the number of items
r is the unique arrangements.

Plug in n = 17 and r = 3
17C3  2  17!
  3!(17 - 3)!

Factorial Formula:

n! = n * (n - 1) * (n - 2) * .... * 2 * 1

Calculate the numerator n!:

n! = 17!

17! = 17 x 16 x 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

17! = 355,687,428,096,000

Calculate (n - r)!:

(n - r)! = (17 - 3)!

(17 - 3)! = 14!

14! = 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

14! = 87,178,291,200

Calculate r!:

r! = 3!

3! = 3 x 2 x 1

3! = 6

Calculate 17C3
17C3  =  355,687,428,096,000
  6 x 87,178,291,200

17C3  =  355,687,428,096,000
  523,069,747,200

17C3 = 680



Excel or Google Sheets formula:

=COMBIN(17,3)

What is the Answer?

17C3 = 680

How does the Permutations and Combinations Calculator work?

Free Permutations and Combinations Calculator - Calculates the following:
Number of permutation(s) of n items arranged in r ways = nPr
Number of combination(s) of n items arranged in r unique ways = nCr including subsets of sets
This calculator has 2 inputs.

What 2 formulas are used for the Permutations and Combinations Calculator?

nPr=n!/r!
nCr=n!/r!(n-r)!

For more math formulas, check out our Formula Dossier

What 4 concepts are covered in the Permutations and Combinations Calculator?

combination
a mathematical technique that determines the number of possible arrangements in a collection of items where the order of the selection does not matter
nPr = n!/r!(n - r)!
factorial
The product of an integer and all the integers below it
permutation
a way in which a set or number of things can be ordered or arranged.
nPr = n!/(n - r)!
permutations and combinations

Example calculations for the Permutations and Combinations Calculator

Permutations and Combinations Calculator Video


Robert Thorne
Author

Robert Thorne

Robert Thorne covers electric vehicle innovations, autonomous driving systems, global mobility trends, and automotive engineering developments.