At what rate percent of simple interest will a sum of money double itself in 77 years? Choose the correct choice.
A) 6.54 % B) 2.54 % C) 8 . 2 % D) 4.94 % E) 1.29 %

Rationale: let sum = x . then , s . i . = x . rate = ( 100 * s . i . ) / ( p * t ) = ( 100 * x ) / ( x * 77 ) = 100 / 77 = 1.29 % answer : e
Answer: E