Question

Monica has a C.D. Account in the Union Bank of India and deposited Rs 600 per month .

If the maturity value of this account is Rs 24,930 and the rate of interest is 10% per

annum ; find the time (in years) for which the account was held.

Answer 1

Answer:

36 mont

Step-by-step explanation:

Given Monica has a C.D. Account in the Union Bank of India and deposited Rs 600 per month .  If the maturity value of this account is Rs 24,930 and the rate of interest is 10% per  annum ; find the time (in years) for which the account was held.  

Given per month deposit = Rs 600

Rate of interest = 10%

number of months = n

So we have I = P x n(n + 1)/2 x 12 x r / 100

                 I = 600 x n(n + 1) / 24 x 10 / 100

               I = 5 n (n + 1) / 2

Given maturity value is 24,930

  (600 x n) + 5 n(n + 1) / 2 = 24,930

 5 n^2 + 1205 n - 49,860 = 0

  n = - b  ± √b² - 4 a c /2 a

    = - 1205 + √2449225 / 10

 n = 360/10

n = 36 months or 3 years

Answer 2

Answer:

3yrs

Step-by-step explanation:

n can't be negative. Therefore the time for which the account was held is 36 months or 3 years.