[Solved] Calculating values in a query

[blokkendoos]

In a form I calculate the VAT with a macro. But before I started using the form I calculated the VAT in a query.
The outcome of these different calculations differed at most 9 cents.
Somehow something went wrong.
The query calculation used the following calculation (T / (100 + v)) * v
The form calculation, checked with Calc, seemed right.
So I changed the query calculation to: (T * v) / (100 + v) and this produces the same outcome as the form calculation!!

Can someone please explain the difference?
T = total including vat
v = vat percentage in the form of an integer (i.e. 19)

tia
pablo k

[TheGurkha]

Let S = 100 + v.

What you were doing in (T / (100 + v)) * v was equivalent to ( T / S ) * v

But (T * v) / (100 + v) is equivalent to ( T * v) / S. Note the swapping of the multiply and the divide in the end results.

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