Question 12 Marks
Sharukh opened a recurring deposit account in a bank and deposited $Rs.800$ per month for $1 \frac{1}{2}$ years. If he recieved $Rs.15,084$ at the time of maturity, find the rate of interest per annum
Answer
View full question & answer→Monthly deposit (P) $= Rs.800$
$n =\frac{3}{2} \times 12 \text { months }=18 \text { months }$
Maturity value (M.V) $= Rs.15084$
Now, M.V $=P \times N+P \times \frac{n(n+1)}{2 \times 12} \times \frac{r}{100}$
$\Rightarrow 15084=800 \times 18+800 \times \frac{18 \times 19}{24} \times \frac{r}{100} $
$ \Rightarrow 15084=14400+114 r $
$ \Rightarrow 114 r=684 $
$\Rightarrow r=\frac{684}{114}=6 \%$
Thus, the rate of interest per anum is $6\%.$
$n =\frac{3}{2} \times 12 \text { months }=18 \text { months }$
Maturity value (M.V) $= Rs.15084$
Now, M.V $=P \times N+P \times \frac{n(n+1)}{2 \times 12} \times \frac{r}{100}$
$\Rightarrow 15084=800 \times 18+800 \times \frac{18 \times 19}{24} \times \frac{r}{100} $
$ \Rightarrow 15084=14400+114 r $
$ \Rightarrow 114 r=684 $
$\Rightarrow r=\frac{684}{114}=6 \%$
Thus, the rate of interest per anum is $6\%.$