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.
[(2((29)^(-1))(10^((29)-1)-1))]mod 90 = 72
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random