We're entering the realm of HTML and CGI problems. If it works with a text input field but does not work with a radio button, my first instinct is that you do not have your HTML form built correctly.

<input type='text' name='number'>
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If that works, your corresponding radio buttons should look something like this:

<input type='radio' name='number' value='1'>
<input type='radio' name='number' value='2'>
...
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Verify that this is correct, and if you're still having problems, we need more information. You posted nothing at all CGI or HTML related, so we have nothing to go on in helping you solve your problem.