Question

you buy a sandwich for $6.965, a salad for $3.25, and a drink for $1.79. if sales tax is 7%, how much change do you receive from $20 bill, rounded to the nearest cent?

Answer 1

6.965 + 3.25 + 1.79 = 12.005, now, let's apply a 7% taxation on that

$\begin{array}{|c|ll} \cline{1-1} \textit{a\% of b}\\ \cline{1-1} \\ \left( \cfrac{a}{100} \right)\cdot b \\\\ \cline{1-1} \end{array}~\hspace{5em}\stackrel{\textit{7\% of 12.005}}{\left( \cfrac{7}{100} \right)12.005}\implies 0.84035~\hfill \underset{total~bill}{\stackrel{12.005~~ + ~~0.8435}{12.84535}} \\\\\\ 20~~ - ~~12.84535\implies 7.15465~~\approx ~~ \ 7.15$