how do I calculate 40.000 nCr 20.000?
You obviously have internet access. It took me less than 10 seconds to find a site to give that info.
40C20=137,846,528,820. You have to have a calculator that has Permutations and Combinations keys in it.
If your numbers are: 40,000NCR20,000
=6.32024495618486 x 10^12,038
