Question

At what rate per cent compound interest per annum will rs 16000 amoumt to rs 22781.25 in 3 year

Answer 1

Q1) Compute the amount and the compound interest in each of the following by using the formulae when:

(i) Principal = Rs 3000, Rate = 5%, Time = 2 years

(ii) Principal = Rs 3000, Rate =18%, Time = 2 years

(iii) Principal = Rs 5000, Rate = 10 paise per rupee per annum, Time = 2 years

(iv) Principal = Rs 2000, Rate = 4 paise per rupee per annum, Time = 3 years

(v) Principal = Rs 12800, Rate =712%, Time = 3 years

(vi) Principal =Rs 10000, Rate 20% per annum compounded half-yearly, Time = 2 years

(vii) Principal = Rs 160000, Rate =10 paise per rupee per annum compounded half-yearly, Time = 2 years.

Solution:

Applying the rule A =P(1+R100)n on the given situations, we get:

(i) A =3000(1+5100)2 =3000(1.05)2 = Rs 3307.5

Now, CI = A – P = Rs 3307.50 – Rs 3000 = Rs. 307.50

(ii) A =3000(1+18100)2 =3000(1.18)2 = Rs 4177.2

Now, CI = A – P = Rs 4177.20 – Rs 3000 = Rs. 1177.20

(iii) A =5000(1+10100)2 =5000(1.10)2 = Rs 6050

Now, CI = A – P = Rs 6050 – Rs 5000 = Rs. 1050

(iv) A =2000(1+4100)3 =2000(1.04)3 = Rs 2249.68

Now, CI = A – P = Rs 2249.68 – Rs 2000 = Rs. 249.68

(v) A =12800(1+7.5100)3 =12800(1.075)3 = Rs 15901.40

Now, CI = A – P = Rs 15901.40 – Rs 12800 = Rs. 3101.40

(vi) A =10000(1+20200)4 =10000(1.1)4 = Rs 14641

Now, CI = A – P = Rs 14641 – Rs 10000 = Rs. 4641

(vii) A =160000(1+10200)4 =160000(1.05)4 = Rs 194481

Now, CI = A – P = Rs 194481 – Rs 160000 = Rs. 34481

Q2) Find the amount of Rs 2400 after 3 years, when the interest is compounded annually at the rate of 20% per annum.

Solution:

Given:

P = Rs 2400

R = 20 % p.a

n = 3 years

We know that amount A at the end of n years at the rate R% per annum when the interest is compounded annually is given by

A =P(1+R100)n

A =2400(1+20100)3

A =2400(1.2)3

A = 4147.20

Thus, the required amount is Rs 4147.20.

Answer 2

Ur answer is 4147.20.