A sum of money becomes triple itself in 5 years at simple interest. How many years will it become nine times at the same rate?
Choose the correct option: A) 12 Â½ years B) 62 Â½ years C) 18 Â½ years D) 72 Â½ years E) 12 Â½ years
100 ---- 200 ---- 5   200 ---- 5   100 ---- 2 1/2   ------------------   900 ---- 18 Â½ years   Answer:18 Â½ years
<result>C</result>
A sum of money becomes triple itself in 5 years at simple interest. How many years will it become nine times at the same rate?