Question

There is a 60% increase in an amount in 6 years at simple interest. What will be the compound interset on Rs 12,000 after 3 years at the same rate?

• A. Rs 2160
• B. Rs 3120
• C. Rs 3972
• D. Rs 6240

Answer 1

The correct option is C Rs 3972

I for 6 years an SI $=\frac{Pr16}{100}$
Amount after 6 years $=P+\frac{Pr\times 6}{100}=P(1+\frac{6r}{100})\text{/}P(1+\frac{6r}{100})=P+60\%P=1.6\text{/}P\therefore 1+\frac{6r}{100}=1.6or\frac{6r}{100}=0.6r=\frac{0.6\times 100}{6}=10\%$
$\therefore$ CI for 3 years an 12000 (a) 10%
$=12000{(1+\frac{10}{100})}^s-12000=12000\left\{\right(1.1{)}^3-1\}=12000\{1.331-1\}=12000\times 0.331=3972000$
=Rs 3972