Question:
A certain sum amounts to Rs. 2,400 in 2 years and Rs. 2,800 in 5 years under simple interest. Find the principal amount.
कोई निश्चित धनराशि साधारण ब्याज पर 2 वर्षों में 2,400 रुपये और 5 वर्षों में 2,800 रुपये हो जाती है। मूलधन राशि ज्ञात कीजिए।
Options:
- Rs. 1,800
- Rs. 1,900
- Rs. 2,000
- Rs. 2,133.33
- Rs. 1,800
- Rs. 1,900
- Rs. 2,000
- Rs. 2,133.33
Correct Answer: d)
Explanation:
Interest for \(5 – 2 = 3\text{ years} = 2800 – 2400 = \text{Rs. } 400\).
Interest per year = \(\dfrac{400}{3} = \text{Rs. } 133.33\).
Interest for 2 years = \(2 \times \dfrac{400}{3} = \text{Rs. } 266.67\).
Principal = \(2400 – 266.67 = \text{Rs. } 2,133.33\).
3 वर्षों का साधारण ब्याज = \(2800 – 2400 = 400\text{ रुपये}\)।
1 वर्ष का ब्याज = \(\dfrac{400}{3}\text{ रुपये}\)।
2 वर्षों का ब्याज = \(\dfrac{800}{3} = 266.67\text{ रुपये}\)।
मूलधन = \(2400 – 266.67 = 2,133.33\text{ रुपये}\)।