Braun invested a certain sum of money at 8% p.a. simple interest for 'n' years. At the end of 'n' years, Braun got back 3 times his original investment. What is the value of n?	Choose the correct answer:
A) 50 years  B) 25 years  C) 12 years 6 months  D) 37 years 6 months  E) 40 years
Explanatory Answer   Let us say Braun invested $100.   Then, at the end of 'n' years he would have got back $300.   Therefore, the Simple Interest earned =300 - 100= 
<gadget id="calculator">300 - 100</gadget>
<output>200</output>
$200.   We know that Simple Interest= (Principal * number of years * rate of interest) / 100   Substituting the values in the above equation we get 200 = (100 * n * 8) / 100   Or 8n = 200   Or n = 25 years.   correct choice is (25 years)
<result>B</result>
Braun invested a certain sum of money at 8% p.a. simple interest for 'n' years. At the end of 'n' years, Braun got back 3 times his original investment. What is the value of n?