The simple interest on Rs 300 increases by Rs 15 when the rate of interest increases by 4% per annum. What is the time period?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → \(1\frac{1}{4}\) years
For the same principal and time, the extra interest is simple interest at the extra rate alone.
Extra interest at 4% per annum on Rs 300 for \(T\) years \(\displaystyle =\frac{300\times4\times T}{100}=12T\)
\(12T=15\)
\(\displaystyle T=\frac{15}{12}=1\frac{1}{4}\) years
The time period is \(1\frac{1}{4}\) years.