In what time a sum of money double itself at 4% per annum simple interest?
Pick one: A) 25 % B) 33 1 / 3 % C) 83 1 / 3 % D) 33 4 / 3 % E) 73 1 / 3 %

Rationale: "p = ( p * 4 * r ) / 100 r = 25 % answer : a"
Answer: A