Question

a man gets Rs 6455 at the end of one year at the rate of 14% per annum in a  recurring deposit account.Find the monthly instalment.

Answer 1

let monthly installment = x

total money paid = x * 12months

interest = maturity value - total money paid

= 6455 - 12x

interest = P[n(n+1)/2 * 1/12 * R/100]

i = P [12*13/2 * 1/12 * 14/100]

6455-12x = x[7*13/100]

6455 - 12x = 91/100x

6455 = 12.91x
x = Rs. 500

Answer 2

Think of ₹ P as a monthly in stallment

Duration (x) = 1 year = 12 months

We know that

Total monthly head = = × (x (x + 1)] / 2

Enter the value of x

= P × (12 × 13) / 2

With continuous calculation

= 78P

Interest = PRT / 100

Pricing

= (78P × 14 × 1) / (100 × 12)

So we get it

= 0.91P

So the maturity value = P × x + SI

6455 = P × 12 + 0.91P

6455 = 12.91P

With continuous calculation

P = 6455 / 12.91 = ₹ 500