Question

A sum of money is accumulating at compound interest at a certain rate of interest. If simple interest instead of compound were reckoned, the interest for the first two years would be diminished by ₹ 20 and that for the first three years, by 61. What is the sum?

• A. ₹ 7500
• B. ₹ 7000
• C. ₹ 8000
• D. ₹ 6500

Answer 1

The Correct Option is C

P - sum and r- rate of interest

Simple Interest \(=\frac{prt}{100}\)

Compound interest:

Amount \(=P(1+\frac{r}{100})^n\)

\(p(\frac{r}{100})^2=40\)

\(P(\frac{r}{100})^2\times\frac{(300+r)}{100}=61\)

On Solving, we get

P= 8000 (sum). So the correct option is (C)