How do I make forms in Frontpage that can do its own calculations?

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From: Hester (Hester_at_discussions.microsoft.com)
Date: 10/01/04 

Date: Fri, 1 Oct 2004 07:11:07 -0700

I am trying to make a form in Frontpage 2000 that can add up the items.

So they can order tickets on line. So I need how many tickets x $ =

HELP! Very new at this...but willing to learn