Question

Sally was the waitress at two tables. At the first table the bill came to $38.70 and the tip was 15%. At the second table the bill came to $33.45 but the tip was 20%. At which table did Sally receive a larger gratuity? By how much was it larger? ​

Answer 1

$\bf \begin{array}{|c|ll} \cline{1-1} \textit{a\% of b}\\ \cline{1-1} \\ \left( \cfrac{a}{100} \right)\cdot b \\\\ \cline{1-1} \end{array}~\hfill \stackrel{\textit{15\% of 38.70}}{\left( \cfrac{15}{100} \right)38.70}\implies \underline{5.805}~\hfill \stackrel{\textit{20\% of 33.45}}{\left( \cfrac{20}{100} \right)33.45}\implies \stackrel{\textit{larger}}{\underline{6.69}} \\\\\\ \stackrel{\textit{by how much?}}{6.69-5.805\implies 0.885}$