Can I add 2 fields in 1 table and auto fill the answer in a third field?

[Jeff]

I have 5 fields in my table, all are currency entries. Its basically
Merchandise plus labor equals sub total. then add sales tax, then computing
the total and filling the final field

5 fields, A through E
Field A + field B = field C
Field C multiplied by .07 = Field D
Field C + field D = field E

I use a form to add info to the table but would like to know if it can
update the other fields in the table automatically.
I was able to do this on the form using an expression builder in the control
of the text box.
But I don't know if it can update the respective fields in the table
automatically.
Can it do this? And if so could anyone steer me toward my desired result

As always, thanks in advance for any help. Jeff

 

[fredg]

I have 5 fields in my table, all are currency entries. Its basically
Merchandise plus labor equals sub total. then add sales tax, then computing
the total and filling the final field

5 fields, A through E
Field A + field B = field C
Field C multiplied by .07 = Field D
Field C + field D = field E

I use a form to add info to the table but would like to know if it can
update the other fields in the table automatically.
I was able to do this on the form using an expression builder in the control
of the text box.
But I don't know if it can update the respective fields in the table
automatically.
Can it do this? And if so could anyone steer me toward my desired result

As always, thanks in advance for any help. Jeff

You're using Access, not Excel.
There is no need to store the results of the calculation.
As long as you have FieldA and FieldB stored in a table, anytime you
need the Subtotal or Total, simply calculate it.

In a query:
Total[FieldA] + [FieldB])*1.07

Do not store this value.

Directly on a form or in a report, use an unbound text control.
Set it's control source to:
=([FieldA] + [FieldB])*1.07