Management Aptitude Test 2014 Paper

(c) Let original price of petrol = ₹ x per gallon
After deduction, price of petrol = ₹ x × $\frac{90}{100}=\mathrm{₹}\frac{9}{10}\mathit{x}$
Now, according to the question
$\frac{1800}{\frac{9}{10}\mathit{x}}-\frac{1800}{\mathit{x}}$ = 5
⇒ $\frac{2000}{\mathit{x}}-\frac{1800}{\mathit{x}}$ = 5
⇒ $\frac{200}{\mathit{x}}=5$
⇒ $\mathit{x}=\frac{200}{5}$
∴ x = ₹ 40
Hence, original price of petrol = ₹ 40 per gallon