Harpreet invested ₹12,000 and received ₹2,880 as simple interest after 4 years. What was the rate of interest per annum?

Explanation

1. 01

   $R = \frac{\text{SI} \times 100}{P \times T} = \frac{2880 \times 100}{12000 \times 4}$.

2. 02

   $R = \frac{288000}{48000} = 6\%$ per annum.