Question

find the interest on ₹6200 at 3% per annum for 3 years ​

Answer 1

Step-by-step explanation:

Let A be the amount and R be the interest, compounding annual

A x ((100 + R)÷100)^ 2 = 6200

A x ((100+R)÷100)^3 = 7400

Now

2÷ 1,

(100 + R)÷100 = 7400÷6200

100 + R =( 74÷62. ) X 100

100 + R = 119.3548387097

R = 19.3548387097

To find Amount,

A x( 119.3548387097/100)^2 =6200.

A x 1.4245577523= 6200

A = 6200÷1.4245577523

4,352.2279037055

in case of simple interest

Let us take the question as involving simple interest.

Let P be the principal and R as interest rate.

Now

P + (P x 2 x R/100) = 6200

P + (Px 3xR/100) = 7400

(2) - (1)

3PR/100 - 2PR/100 = 7400 - 6200= 1200.

PR/ 100 = 1200.

(2) + (1)

2P + 3PR/100 + 2PR/100 = 7400 + 6200 = 13600.

2P + 5PR /100 = 13600.

Substituting for PR /100 as 1200.

2P +( 5 × 1200) =13600.

2P = 13600 - 6000= 7600.

P = 3800.

we have,

PR/100 = 1200.

3800× R /100 = 1200

R = 1200÷38,

31.58.

Hence the principal is 3800 and interest rate is 31.58.