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.
Sum[n(1-1/1200)^(n-1)*(1/1200),{n,1,1500}]/0.714
Sum[n(1-1/1200)^(n-1)*(1/1200),{n,1,1500}]/0.714
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random