Question

Kavita has a cumulative time deposit account in a bank. She deposits ₹800per month and gets ₹16700as maturity value .If the rate of interest be 5percent per annum , find the total time for which the account was held​

Answer 1

Answer:

20 months.

Step-by-step explanation:

Solution this sum is photo.

Answer 2

Let time be x months

Qualifying amount

= 800x(x+1)/2 = 400x(x+1)

SI = 400x(x+1)*5*1/1200

= (1/3)x(x+1)*5

= (5/3)x(x+1)

Principal = 800x

Hence,

800x + (5/3)x(x+1) = 16700

2400x + 5x = 16700*3

x² + 481x - 10020 = 0

x² + 501x - 20x - 10020 = 0

x(x + 501) -20(x + 501)

Negative value not possible

Therefore, time for which account is held = 20 months

hope it's help you