Question

3 How much would a $15.99 book cost if

your state sales tax is 5.65%?
A $18.45
C $20.64
B $16.89
D $16.35

Answer 1

well, is simply the price plus tax, so

`\begin{array} \cline{1-1} \textit{\textit{\LARGE a}\% of \textit{\LARGE b}}\\ \cline{1-1} \\ \left( \cfrac{\textit{\LARGE a}}{100} \right)\cdot \textit{\LARGE b} \\\\ \cline{1-1} \end{array}~\hspace{5em}\stackrel{\textit{5.65\% of 15.99}}{\left( \cfrac{5.65}{100} \right)15.99} ~~ \approx ~~ 0.90~\hfill \underset{total~cost}{\stackrel{15.99~~ + ~~0.90}{\approx\text{\LARGE 16.89}}}`