Question

Rajan bought a watch for Rs 1870 including VAT at 10%. Find the original price of the watch.

Answer 1

​ $$\begin{gathered} \mathrm{Let}\mathrm{the}\mathrm{original}\mathrm{price}\mathrm{be}\mathrm{Rs}x. \\ \mathrm{VAT}=10\%\mathrm{of}\mathrm{Rs}x \\ =\mathrm{Rs}\left(\mathrm{x}\times \frac{10}{100}\right) \\ =\mathrm{Rs}\frac{\mathrm{x}}{10} \\ \therefore \mathrm{Price}\mathrm{including}\mathrm{VAT}=\mathrm{Rs}\left(\mathrm{x}+\frac{\mathrm{x}}{10}\right) \end{gathered}$$
$=\mathrm{Rs}.\frac{11x}{10}$
$\therefore \frac{11x}{10}=1870$
$$\begin{gathered} \Rightarrow x=\left(1870\times \frac{10}{11}\right) \\ \Rightarrow x=1700 \end{gathered}$$
$\therefore \mathrm{The}\mathrm{original}\mathrm{price}\mathrm{of}\mathrm{the}\mathrm{watch}\mathrm{is}\mathrm{Rs}1,700.$