At what rate percent per annum will a sum of money double in 16 years.	Answers:  A) 2.45 %  B) 5.62 %  C) 5.35 %  D) 6.9 %  E) 6.25 %

Rationale: "let principal = p then s . i . = p t = 16 yrs rate = ( 100 * p ) / ( p * 16 ) = 25 / 4 = 6.25 % p . a . answer is e"
Answer: E