Enter the total number of items and the number of items to choose into the calculator to determine the number of combinations. This calculator can also evaluate any of the variables given the others are known.

C To Nc Formula

The following formula is used to calculate the number of combinations (Nc) from a set of items (C).

Nc = C! / (n!(C-n)!) 

Variables:

  • Nc is the number of combinations
  • C is the total number of items
  • n is the number of items to choose
  • ! denotes factorial, which is the product of all positive integers up to that number

To calculate the number of combinations, first calculate the factorial of the total number of items. Then, calculate the factorial of the number of items to choose and the factorial of the difference between the total number of items and the number of items to choose. Finally, divide the factorial of the total number of items by the product of the other two factorials.

How to Calculate C To Nc?

The following steps outline how to calculate the number of combinations (Nc) using the formula Nc = C! / (n!(C-n)!).


  1. First, determine the total number of items (C).
  2. Next, determine the number of items to choose (n).
  3. Next, calculate the factorial of C, denoted as C!.
  4. Next, calculate the factorial of n, denoted as n!.
  5. Next, calculate the factorial of (C-n), denoted as (C-n)!
  6. Finally, calculate the number of combinations (Nc) using the formula Nc = C! / (n!(C-n)!).
  7. After inserting the values of C and n into the formula and calculating the result, check your answer with a calculator or by using the example problem below.

Example Problem:

Use the following variables as an example problem to test your knowledge:

Total number of items (C) = 6

Number of items to choose (n) = 3