Question

The compound interest on Rs. $8000$ for $1$ year at $5$ %p.a. payable half-yearly is:

• A. Rs. $800$
• B. Rs. $810$
• C. Rs. $400$
• D. Rs. $405$

Answer 1

Answer: (D)

Rs. $405$

$P=$ Rs.$8000$, Time $=1$ year, R$=5$ $\%$ payable half-yearly

Amount $=P{(1+\frac{R}{100})}^t$

$\Rightarrow 8000{(1+\frac{5}{2\times 100})}^2$

$\Rightarrow 8000\times {(1+\frac{1}{40})}^2$

$\Rightarrow 8000\times \frac{41}{40}\times \frac{41}{40}$

$\Rightarrow 41\times 41\times 5=$ Rs. $8405$

C.I $=$ Amount $-$ Principal

C.I $=8405-8000=$ Rs. $405$