Question

The compound interest on a certain sum for 2 years is rs. 786 and s.i. is rs. 750. if the sum is invested such that the s.i. is rs. 1296 and the number of years is equal to the rate per cent per annum, find the rate of interest?

Answer 1

1296-750=546
786/546=(1+r/100)^2
131/91^2=100+r/100
u can solve after tat

Answer 2

Answer:

Rate of interest is 60%

Step-by-step explanation:

Given : The compound interest on a certain sum for 2 years is rs. 786 and s.i. is rs. 750.

If the sum is invested such that the s.i. is rs. 1296 and the number of years is equal to the rate per cent per annum.

To find: The rate of interest?

Solution :

Compound interest for 2 years = Rs. 786

Simple interest for 2 years = Rs. 750

Interest for 2 years is

$I=\frac{CI-SI}{n}\times 100$

$I=\frac{36}{360}\times 100$

$I=10\%$

P for first year = 3600

Let the time and rate = x

$I=P\times R\times T$

$1296=3600\times x\times x$

$0.36=x^2$

$x=0.6$

In percentage,

$x=0.6\times 100=60\%$

The rate of interest is 60%.