# Combination Calculator

## Calculates the number of combinations of n things taken r at a time.

 number of things n n≧r≧0 number to be taken r 6dgt10dgt14dgt18dgt22dgt26dgt30dgt34dgt38dgt42dgt46dgt50dgt combinations nCr
 $\normal Combinations\\\vspace{5}(1)\ {}_nC_r=\left$$n\\r\\ \right$$={\large\frac{n!}{r!(n-r)!}}\\(2)\ {}_nC_r={\large\frac{{}_nP_r}{r!}}\\$

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