Question

There is 60% increase in an amount in 6 years at simple interest. what will be the compound interest of rs. 12,000 after 3 years at the same rate?

a.rs. 2160

Answer 1

60% in 7 years so 60/6=10% per year
p=12000, r=10 %,t=3 years
putting these values in A=P (1+R/100)n
compound interest =A-P

Answer 2

The amount at the end of 'n' years of investing in compound interest.

$A = P(1 + \frac{r}{100} {)}^{n}$

$here,$

$P = 12000$

$n = 3$

$r = 5\%$

$A = 12000(1 + \frac{5}{100} {)}^{3}$

$= rs.13891.5$

now, compound interest

$CI = amount - principle \\ = 13891.5 - 12000 \\ \boxed{= rs.1891.5}$