Question

The price of books are $180 but he uses a 30% discount but there is a 4% tax what is the total price?

Answer 1

well, so the book is 180 and is discounted by 30%, how much will that be?

$\begin{array}{|c|ll} \cline{1-1} \textit{a\% of b}\\ \cline{1-1} \\ \left( \cfrac{a}{100} \right)\cdot b \\\\ \cline{1-1} \end{array}~\hspace{5em}\stackrel{\textit{30\% of 180}}{\left( \cfrac{30}{100} \right)180}\implies 54\qquad \qquad \underset{\textit{discounted price}}{\stackrel{180-54}{126}}$

so from that discounted price, a tax of 4%

$\begin{array}{|c|ll} \cline{1-1} \textit{a\% of b}\\ \cline{1-1} \\ \left( \cfrac{a}{100} \right)\cdot b \\\\ \cline{1-1} \end{array}~\hspace{5em}\stackrel{\textit{4\% of 126}}{\left( \cfrac{4}{100} \right)126}\implies 5.04\qquad \qquad \underset{\textit{final price}}{\stackrel{126+5.04}{131.04}}$