34
Arithmetic
• Compound Interest
चक्रवृद्धि ब्याज पर एक धनराशि 2 वर्षों में ₹7,200 और 3 वर्षों में ₹8,640 हो जाती है। मूलधन कितना था?
A sum becomes ₹7,200 in 2 years and ₹8,640 in 3 years at compound interest. What was the original principal?
सही उत्तर: B
Correct Answer: B
एक वर्ष का वृद्धि गुणक = 8640/7200 = 1.2, इसलिए ब्याज दर 20% है। मूलधन = 7200/(1.2)² = 7200/1.44 = ₹5,000।
The annual growth factor is 8640/7200 = 1.2, so the interest rate is 20%. The principal is 7200/(1.2)² = ₹5,000.