## How to Calculate Combinations ?

**Important Note : To calculate combinations,**

**First you should calculate all the equivalent permutations.****Later you should correct this list by cutting out duplicates / repetitions.**

** **Now lets have a look at the mathematical formula for Combinations..

^{n}C_{r} = |
n! |
= |
n(n – 1)(n – 2) … … r |
. |

(r!)(n – r!) |
r! |

n above case **n** is 4 and **r **is 3, so

^{n}C_{r} = C(n,r) = 4

**That’s all for now friends. In our next post we shall discuss some practice problems on Permutations and Combinations.**