The simple interest on ₹10000 for 15 years at 15% PA is equal to the simple interest on ₹15000 at \(x\)% PA in 10 years. Find the value of \(x\).
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → 15% PA
Simple interest is \(\displaystyle SI=\frac{P\times R\times T}{100}\). Work out the first interest, then set the second interest equal to it.
On ₹10000 for 15 years at 15%:
\(\displaystyle SI=\frac{10000\times15\times15}{100}=22500\)
On ₹15000 for 10 years at \(x\)%:
\(\displaystyle SI=\frac{15000\times x\times10}{100}=1500x\)
\(1500x=22500\), so \(x=15\), that is, 15% PA