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

Answer: (C)

₹ 8000

Answer 2

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)