The interest earned on ₹15,000 in 3 years at simple interest is ₹5,400. Find the rate of interest per annum.
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 12%
Simple interest is reckoned on the principal alone: \(\displaystyle \text{SI}=\frac{P\times R\times T}{100}\), so \(\displaystyle R=\frac{100\times\text{SI}}{P\times T}\).
With SI \(=5400\), \(P=15000\) and \(T=3\): \(\displaystyle R=\frac{100\times5400}{15000\times3}=\frac{540000}{45000}=12\%\)