Question

The price of a book is increased by 12 per cent. If it's increased price is Rs 145.60, find the original price.

Answer 1

$$\begin{gathered} \mathrm{Let}\mathrm{the}\mathrm{original}\mathrm{price}\mathrm{of}\mathrm{the}\mathrm{book}=\mathrm{Rs}x \\ \mathrm{Now},\mathrm{rate}\mathrm{of}\mathrm{increase}=12\% \\ \mathrm{Now},\mathrm{increase}\mathrm{in}\mathrm{price}=12\%\mathrm{of}x=\frac{12}{100}x=\mathrm{Rs}0.12x \\ \mathrm{Now},\mathrm{increased}\mathrm{price}=x+0.12x=\mathrm{Rs}1.12x \\ \mathrm{But}\mathrm{increased}\mathrm{price}=\mathrm{Rs}145.60 \\ \mathrm{so},1.12x=145.60 \\ \Rightarrow x=\frac{14560}{112}=130 \\ \mathrm{So},\mathrm{original}\mathrm{price}\mathrm{of}\mathrm{the}\mathrm{book}=\mathrm{Rs}130 \end{gathered}$$