Question

David opened a Recurring Deposit Account
in a bank and deposited 300 per month
for two years. If he received 7,725 at the
time of maturity, find the rate of interest per
annum.​

Answer 1

Answer:

Rate Of Interest= 7%

Step-by-step explanation:

Answer 2

$\underline{ \underline{{ \huge{ \textbf{Q}}} \mathtt{UESTION -}}}$

David opened a Recurring Deposit Account in a bank and deposited ₹ 300 per month for 2 years. If he received ₹ 7,725 at the time of maturity, find the rate of interest per annum.

$\underline{ \underline{{ \huge{ \textbf{G}}} \mathtt{IVEN -}}}$

• principal amount (P) = ₹ 300
• number of months (n) = 24 months
• maturity value (M.V) = ₹ 7,725

$\underline{ \underline{{ \huge{ \textbf{T}}} \mathtt{O } \: \: \: { \huge{ \textbf{F}}} \mathtt{IND - }}}$

• The rate of interest

$\underline{ \underline{{ \huge{ \textbf{F}}} \mathtt{ORMULA } \: \: \: { \huge{ \textbf{U}}} \mathtt{ SED -}}}$

$\underline{ \boxed { \gray{\mathtt{M.V = P \times n + \frac{P \times n(n + 1)}{2 \times 12} \times \frac{r}{100} }}}}$

where,

M.V is the maturity value,

P is the principal amount,

n is the number of months,

r is the rate of interest.

$\underline{ \underline{{ \huge{ \textbf{S}}} \mathtt{OLUTION -}}}$

$\mathtt{M.V = P \times n + \frac{P \times n(n + 1)}{2 \times 12} \times \frac{r}{100} } \\ \\ \mathtt{ \implies{7725 = 300 \times 24 + \frac{300 \times 24(24 + 1)}{2 \times 12} \times \frac{r}{100} }} \\ \\ \mathtt{ \implies{7725 = 7200 + \frac{3 \cancel{0} \cancel{0} \times \cancel{24} ^{ \cancel2} \times 25}{ \cancel{2} \times \cancel{12}} \times \frac{r}{1 \cancel{0} \cancel{0}} }} \\ \\ \mathtt{ \implies{7725 = 7200 + 75 \: r}} \\ \\ \mathtt{ \implies{7725 - 7200 = 75 \: r}} \\ \\ \mathtt{ \implies{525 = 75 \: r}} \\ \\ \mathtt{ \implies{ \frac{ \cancel{525} ^{7} }{ \cancel{75}} = r }} \\ \\ \boxed{ \purple{ \mathtt{ \therefore \: {r = 7 \: \% \: \: \: ans.}}}}$

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@MissSolitary✌️

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