Someone gives me 9900 dollars. Included in the 9900 is 5% is a goods
and services tax. What equation does one use to determine what isn't
tax? If I said that 9900 x 95% = 9405, that would be correct. However,
if I took that same number 9405 and multiplied it by 1.05 to reflect
the 5% tax, I get 9875.25 and not 9900.