Question

5. Milind deposited 64,000 in a savings scheme which fetches him interest at the rate of 7 1/2
compounded annually. After how many years will this sum amount to 79,507?​

Answer 1

Given :-

• Milind deposited Rs 64000

• Rate of interest = 7 1/2

• Sum of amount = Rs 79507

Solution :-

According to the question,

Principal = Rs64000

Rate of interest = 7 1/2 = 15/2

Amount = Rs 79507

As we know that,

A = P ( 1 + R/100)^n

Put the required values in the formula,

79507 = 64000 ( 1 + 15/2 / 100 )^n

79507 = 64000 ( 1 + 15/200 )^n

79507 = 64000 ( 1 + 3 / 40 )^n

79507 = 64000 ( 40 + 3 / 40 )^n

79507 = 64000 ( 43 / 40 )^n

79507 / 64000 = ( 43/40)^n

( 43/40)^3 = ( 43/40)^n

n = 3 years

Hence, After 3 years this sum amount to 79,507$.$

Formula kept in mind :-

• SI = P * R * T / 100

• CI = P ( 1 + R/100)^n