Question

The compound interest on Rs. 2000 for 9 months at 8% per annum being given when the interest is reckoned quarterly is

• A. Rs. 122
• B. Rs. 130
• C. Rs. 150
• D. Rs. 145

Answer 1

The correct option is A

Rs. 122

$P=2000,R=8\%p.a,t=9months=\frac{9}{12}=\frac{3}{4}year$
Since the principal is compounded quartely, R = $\frac{8}{4}$ , n = $4\times \frac{3}{4}$

$C.I=P[{(1+\frac{R}{100})}^n-1]$
$C.I=2000[{(1+\frac{8}{100\times 4})}^{4\times \frac{3}{4}}-1]$ (compounded quarterly)
$=2000[{\left(\frac{102}{100}\right)}^3-1]=Rs.122$
$\therefore$ the compound interest is Rs. 122