SSC Sample Paper Mock Test-6 SSC CGL Tear-II Paper-1

The simple interest on a sum of money at 4% per annum for 2 yr is Rs. 80. The compound interest in the same sum for the same period is

A) Rs. 82.60

B) Rs. 82.20

C) Rs. 81.80

D) Rs. 81.60

Correct Answer: D

Solution :

Principal \[=\frac{\text{SI }\!\!\times\!\!\text{ 100}}{\text{Time }\!\!\times\!\!\text{ Rate}}=\frac{80\times 100}{2\times 4}\]= Rs. 1000

\[\therefore \]\[CI=P\left[ {{\left( 1+\frac{R}{100} \right)}^{T}}-1 \right]=1000\left[ {{\left( 1+\frac{4}{100} \right)}^{2}}-1 \right]\]

\[=1000\left[ {{\left( \frac{26}{25} \right)}^{2}}-1 \right]=1000\left( \frac{676}{625}-1 \right)\]

\[=1000\left( \frac{676-625}{625} \right)=\frac{1000\times 51}{625}\]= Rs. 81.60