चावल के प्रति किलो मूल्य में 25% की वृद्धि के परिणामस्वरूप, एक व्यक्ति ₹ 1,200 में 6 किलो कम चावल खरीद पाता है। चावल का प्रति किलो प्रारंभिक मूल्य क्या था?
Read this question in English
As a result of 25% hike in the price of rice per kg, a person is able to purchase 6 kg less rice for ₹ 1,200. What was the original price of rice per kg?
(a) ₹ 30 · (b) ₹ 40 · (c) ₹ 50 · (d) ₹ 60
उत्तर और व्याख्या · explanation in English
Answer: (b) ₹ 40
A 25% price rise means the same money buys 1/1·25 = 4/5 of the earlier quantity, i.e. 1/5 less. That lost fifth is 6 kg, so ₹ 1,200 used to buy 30 kg, at ₹ 40 a kg.
- New price = 5/4 of old, so quantity for ₹ 1,200 becomes 4/5 of the old quantity — a fall of 1/5.
- 1/5 of old quantity = 6 kg, so old quantity = 30 kg.
- Original price = 1,200 ÷ 30 = ₹ 40 per kg.
- Check: new price ₹ 50 buys 1,200 ÷ 50 = 24 kg, which is 6 kg less.
Remember · Price up by 1/n means quantity down by 1/(n + 1) for the same spending; here 25% = 1/4, so quantity falls by 1/5.
Question and answer: UPSC's official GS Paper II (2020, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·