Paritosh borrowed Rs.8000 at 4% simple interest and Arunesh borrowed Rs.6000 at 6% simple interest. After how much time they will have equal debts? परितोष ने रू. 8000 को 4% वार्षिक साधारण ब्याज की दर से तथा अरूणेश ने रू. 6000 को 6% वार्षिक साधारण ब्याज की दर से उधार लिया। कितने समय बाद दोनों का ऋण बराबर हो जाएगा?

Let t years be when debts are equal. Paritosh's debt after t years: 8000 + 8000 × 0.04 × t = 8000 + 320t. Arunesh's debt after t years: 6000 + 6000 × 0.06 × t = 6000 + 360t. Equating: 8000 + 320t = 6000 + 360t. Solving: 2000 = 40t, giving t = 50 years. After 50 years, Paritosh owes 8000 + 320(50) = 8000 + 16000 = 24000, and Arunesh owes 6000 + 360(50) = 6000 + 18000 = 24000, making option D correct.