The price of sugar having gone down by 10\%, Sharad can buy 6.2 kg more for ₹ 279. The difference between the original and the reduced price (per kg) is
(a)₹ 0.50
(b)₹ 1
(c)₹ 1.50
(d)₹ 4.50
Answer
Answer (as printed): A
Explanation
Let original price $=₹ x$ per kg. Reduced price $$=₹\left(\frac{90 x}{100}\right) \text { per } \mathrm{kg} . \therefore \frac{279}{\left(\frac{90 x}{100}\right)}-\frac{279}{x}=6.2 \Leftrightarrow \frac{27900}{90 x}-\frac{279}{x}=6.2 \begin{aligned} & \Leftrightarrow 27900-25110=6.2 \times 90 x \\ & \Leftrightarrow 558 x=2790 \Leftrightarrow x=5 . \end{aligned}$$ ∴ Required difference $=10 \%$ of ₹ $5=₹ 0.50$.
Explanation as extracted from the printed page; notation may be imperfect.