Simple interest on a certain sum is 16/25 of the sum. Find the rate percent and time, If both are numerically equal. Select the correct option.
A) Rate = 7% and Time = 7 years.
B) Rate = 8% and Time = 8 years.
C) Rate = 6% and Time = 6 years.
D) Rate = 5% and Time = 5 years.
E) None of these
Explanation:   Sol: Let sum = X. Then S.I = 16x/25   Let rate = R% and Time = R years.   Therefore, (x * R * R)/100 = 16x/25 or R^2 = 1600/25, R = 40/5= 
<gadget id="calculator">40/5</gadget>
<output>8</output>
8   Therefore, Rate= 8% and Time = 8 years.   Answer: Rate = 8% and Time = 8 years.
<result>B</result>
Simple interest on a certain sum is 16/25 of the sum. Find the rate percent and time, If both are numerically equal.