# Combinations Calculator

 

An online calculator to calculate the number of combinations of $n$ elements taken $r$ a the time whose formula is given below.

## Formula for the Number of Combinations

The number of combinations of $n$ objects taken in groups of $r$ objects at the time is given by
$n C r = C(n , r) = \dfrac{n!}{(n-r)! r!}$

## Use of Combinations Calculator

1 - Enter the positive integers $n$ (total number of objects) and $r$ (the number of objects in each group) and press "Calculate Combinations".

 (n,r) = 2 , 2