Question

Puneet has a recurring deposit account in a bank and deposits 400 per

month. If he receives 10100 at the time of maturity, find the time for which

the account is held if the rate of interest is 5% p.​

Answer 1

Step-by-step explanation:

Given Puneet has a recurring deposit account in a bank and deposits 400 per month. If he receives 10100 at the time of maturity, find the time for which the account is held if the rate of interest is 5% p.  

• So Deposit per month P = 400
• Rate of interest r = 5%
• Time = n
• So A = P x n + P x n(n + 1) / 2 x 12 x r/100
•         = 400 x n + 400 x n(n + 1) / 24 x 5/100
•        = 400 n + 5n (n + 1) / 6
•  10100 = 2400n + 5n^2 + 5n / 6
•    60600 = 2405 n + 5n^2
•      5n^2 + 2405 n – 60600 = 0
•     n^2 + 481 n – 12120 = 0
•     Using x = - b + - √b^2 – 4ac / 2a we have
•      n = -481 +- √(481)^2 – 4 (1) (-12120) / 2(1)
•        = - 481 + - √231361 + 48480 / 2
•        = - 481 + - 529 / 2
•        =   48 / 2
•      n  = 24
• So the number of months will be 24 months = 2 years.

Reference link will be

https://brainly.in/question/16122745

Answer 2

Step-by-step explanation:

Hope this helps you !!!!!