Geeta needs ₹ 31,800 at the end of 2 years from now. How much money, should she deposit in a recurring deposit account to get the required amount ? The rate of interest is 10%.

Let money deposited per month be ₹ P.

Given,

n = 2 years or 24 months

r = 10%

Maturity Value = 31,800

By formula,

Maturity Value = $P \times n + \dfrac{P \times n(n + 1)}{2 \times 12} \times \dfrac{r}{100}$

Substituting values we get :

$\Rightarrow 31800 = P \times 24 + \dfrac{P \times 24(24 + 1)}{2 \times 12} \times \dfrac{10}{100} \\[1em] \Rightarrow 31800 = P \times 24 + \dfrac{P \times 24 \times 25}{24} \times \dfrac{1}{10} \\[1em] \Rightarrow 31800 = 24P + \dfrac{5P}{2} \\[1em] \Rightarrow 31800 = 24P + 2.5P \\[1em] \Rightarrow 26.5P = 31800 \\[1em] \Rightarrow P = \dfrac{31800}{26.5} \\[1em] \Rightarrow P = 1200.$

Hence, money deposited per month = ₹ 1200.