Uh oh! Wolfram|Alpha doesn't run without JavaScript.
Please enable JavaScript. If you don't know how, you can find instructions
here
.
Once you've done that, refresh this page to start using Wolfram|Alpha.
(0*(75 choose 20-8)+1*(75 choose 20-9)+2*(75 choose 20-10)+1*(75 choose 20-11))/(1*(75 choose 20-8)+4*(75 choose 20-9)+4*(75 choose 20-10)+1*(75 choose 20-11))
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random