Question

Midtown Antiques collects 3​% sales tax on all sales. If total sales including tax are $1028.55, find the portion that is the tax. Round your answer to the nearest cent.

Answer 1

well, the total amount of sales only was really "x", which oddly enough is the 100% of all sales, then we apply 3% tax on "x" and we end up with $1028.55, so 1028.55 is really 100% + 3% = 103%. So what the heck is "x"?

`\begin{array}{ccll} Amount&\%\\ \cline{1-2} x & 100\\ 1028.55& 103 \end{array} \implies \cfrac{x}{1028.55}~~=~~\cfrac{100}{103} \implies 103x=102855 \\\\\\ x=\cfrac{102855}{103}\implies x\approx 998.59`