What formula do I use to show the net value (less 23% tax).

Question

In Numbers, what formula do I use to show the net value (i.e. less 23% tax).

Answer 1

thejuddo writes:
"$100 plus sales tax of 23% would be $123.00 but in order to get the net value of $123.00 less the tax I would have to divide by 1.23 not multiply by 23% and then minus it."
Correct;
The 23% tax is 23 one hundredths of the base amount, and is applied to that amount. As a formula, this can be stated as:
=B2+B2*C2
or
=B2*(1+C2)
(either applying to the data arrangement shown in the top table, and entered in  D2 of that table)
In the other direction, though (bottom table), we start with the Gross amount and the Tax rate as known quantities, from which we are to determine the base amount, remembering that the 23% Tax rate is 23% of the Base amount, not 23% of the Gross amount.
Rewriting the two formulas above as equations, with g, b, and t as the variables, we get:
g = b + (b * t) 
g = b(1+t)
Solving the second for b:
b - g/(1+t)
Expressed as a formula (with the data as arranged in the bottom table, and the formula in D2):
D2: =B2/(1+C2)
In both directions, it may be prudent to round the result to the nearer hundredth, as done here for the calculation immediately above:
=ROUND(B2/(1+C2),2)
Regards,
Barry