In how many years will a sum of money doubles itself at 12% per annum on simple interest?  Choose one:  A) 15%  B) 20%  C) 10%  D) 8%  E) 22%
P = (P*12*R)/100   R = 8%   Answer:8%
<result>D</result>
In how many years will a sum of money doubles itself at 12% per annum on simple interest?