Question

A portable electronic typewriter cost £180 in 1988. Its price rose by 5% in 1989. What was the new price?

Answer 1

`\bf \begin{array}c \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{5\% of 180}}{\left( \cfrac{5}{100} \right)180}\implies 9~\hfill \stackrel{\textit{new price}}{180+9\implies 189}`