“A sum of Rs. 12500 amounts to Rs. 15500 in 4 years at a simple interest rate. What is the rate of interest?”

"To find the simple interest rate use the formula: Simple Interest (SI) = Principal × Rate × Time / 100. Given Principal = 12500 Amount = 15500 Time = 4 years SI = 15500 - 12500 = 3000. Thus 3000 = 12500 × Rate × 4 / 100. Solving Rate = (3000 × 100) / (12500 × 4) = 6%. This calculation is vital in finance for determining loan or investment returns aiding in economic planning and understanding interest-based financial systems."