Question

Simple interest on a sum of money is 1/25 th of the principal and the number of years is equal to the rate of interest per annum. Then the amount after 4 years will be?

Answer 1

Assume as X = number of years and rate of interest per annum, simple Interest (SI) = 1/25, principle = P, time =R.  

SI = (P × T × R) / 100 ⇒ P/25= (P × R × R) / 100 ⇒ P/25= (P × R2) / 100 ⇒ 1/25= (R2) / 100 ⇒ R2 = 100 / 25 ⇒ 2R = 4 ⇒R = 2.