Question

Ci on a certain sum for 2 years is rs. 40.80 and si is rs. 40 for same years. what will be the rate of interest?

Answer 1

Hey there mate!

S. I = PRT/100
=> 40 = P*R*2 /100
=> PR= Rs. 2000


C. I = P(1+R /100)^n - P
=> 40. 80 = P(1 + R/100)^2 - P
=> 200PR +PR^2 = 408000
=> PR(200+ R) = 408000
=> 200+ R = 204
=> R = .( 204 - 200)%
=> R = 4% per annum (ans)

Hope this helps :)