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.
solve (c+r+a) - (c+.9r) / (c+r+a) = .07 for a
solve (c+r+a) - (c+.9r) / (c+r+a) = .07 for a
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random
