Question

if the simple interest on a certain some of money for 2 years be one fifth of the sum then find the rate of interest per annum

Answer 1

Let the sum(or) Principal be x.

Given that Simple interest for 4 years is 1/5th of the sum.

Then the Simple Interest will be x/5.

Given T = 2 years.


We know that Rate of interest = 100 * SI/PT

                                                   = 100 * x/5 /(x * 2)

                                                   = 20/2

                                                   = 10%.


Hope this helps!