Sandy invested a certain sum of money at 12% p.a. simple interest for 'n' years. At the end of 'n' years, Sandy got back 4 times the original investment. What is the value of n?
Choose the correct choice from the following answers.
A) 20 B) 25 C) 30 D) 35 E) 40
n* 0.12 * principal + principal = 4 * principal   n * 0.12 = 3   n = 25 years   The answer is 25.
<result>B</result>
Sandy invested a certain sum of money at 12% p.a. simple interest for 'n' years. At the end of 'n' years, Sandy got back 4 times the original investment. What is the value of n?