If the simple interest on a certain sum of money after 3 1⁄8 years is 1⁄4 of the principal, what is the rate of interest per annum?  Choose the correct choice from the following answers: A) 6% B) 4% C) 8% D) 5% E) 12%
Explanation :   Let the the sum of money(P) be Rs.x   Time(T) = 3 1⁄8 Years = 25⁄8 Years   Simple interest (SI) = x⁄4   Rate of interest per annum(R) = 100×SI/PT=100×x/4/x × 25/8   =100× x ×8/4× x × 25   =8%   Answer : Option 8%
<result>C</result>
If the simple interest on a certain sum of money after 3 1⁄8 years is 1⁄4 of the principal, what is the rate of interest per annum?