How to Automatically Multiply number within the same box???

Hi there,

I'm new to Access and am trying to create a form to use to bill
clients. One of the boxes is a "COURIER" box and what I want to be
able to do is type in the cost of the courier package ie.$10.00 and
have it automatically mulitplied by a set amount ie. 1.5 (50% markup)
so that all that will show will be $15.00 in the box.
I can figure out how to do this easily with 2 boxes, but I don't want
my clients knowing what the markup is.

Can anyone help???

Thanks,
Adam
Regus

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