Question 64:
A sum becomes ₹7,200 in 2 years and ₹8,640 in 3 years at compound interest. What is the original principal?
चक्रवृद्धि ब्याज पर एक राशि 2 वर्षों में ₹7,200 और 3 वर्षों में ₹8,640 हो जाती है। मूल प्रिंसिपल क्या है?
Options:
- a) ₹4,800
- b) ₹5,000
- c) ₹5,200
- d) ₹5,500
- a) ₹4,800
- b) ₹5,000
- c) ₹5,200
- d) ₹5,500
correct answer : b)
Explanation:
Rate of interest = (8640 – 7200) / 7200 = 1440 / 7200 = 20%. P * (1 + 0.2)^2 = 7200 => P * 1.44 = 7200 => P = ₹5,000.
ब्याज दर = (8640 – 7200) / 7200 = 1440 / 7200 = 20%। पी * (1 + 0.2)^2 = 7200 => पी * 1.44 = 7200 => पी = ₹5,000।