Question 1

Find compound interest on Rs. 8000 at 15% per annum for 2 years 4 months, compounded annually

Accepted Answer

Time = 2 years 4 months = 2(4/12) years = 2(1/3) years. Amount = Rs'. [8000 X (1+(15/100))^2 X (1+((1/3)*15)/100)] =Rs. [8000 * (23/20) * (23/20) * (21/20)] = Rs. 11109. . :. C.I. = Rs. (11109 - 8000) = Rs. 3109.

Question 2

A sum of money lent at compound interest for 2 years at 20% per annum would fetch Rs.482 more, if the interest was payable half yearly than if it was payable annually . The sum is

Accepted Answer

Let sum=Rs.x C.I. when compounded half yearly = x 1 + 10 100 4 - x = 4641 10000 C.I. when compounded annually = x 20 100 2 - x = 11 25 4641 10000 x - 11 25 x = 482 => x=20000

Question 3

A sum of money amounts to Rs.6690 after 3 years and to Rs.10,035 after 6 years on compound interest.find the sum.

Accepted Answer

Let the sum be Rs.P.then P(1+R/100)^3=6690…(i) and P(1+R/100)^6=10035…(ii) On dividing,we get (1+R/100)^3=10025/6690=3/2. Substituting this value in (i),we get: P*(3/2)=6690 or P=(6690*2/3)=4460 Hence,the sum is rs.4460.

Question 4

The difference between compound interest and simple interest on a sum for two years at 8% per annum, where the interest is compounded annually is Rs.16. if the interest were compounded half yearly , the difference in two interests would be nearly

Accepted Answer

For 1st year S.I =C.I. Thus, Rs.16 is the S.I. on S.I. for 1 year, which at 8% is thus Rs.200 i.e S.I on the principal for 1 year is Rs.200 Principle = R s . 100 * 200 8 * 1 = Rs.2500 Amount for 2 years, compounded half-yearly R s . 2500 * 1 + 4 100 4 = R s . 2924 . 4 C.I = Rs.424.64 Also, S . I = R s . 2500 * 8 * 2 100 = R s . 400 Hence, [(C.I) - (S.I)] = Rs. (424.64 - 400) = Rs.24.64

Compound Interest Questions