The output of a factory was increased by 10% to keep up with rising demand. To handle the holiday rush, this new output was increased by 25%. By approximately what percent would the output now have to be decreased in order to restore the original output? Pick one:  A) 20 %  B) 24 %  C) 30 %  D) 27 %  E) 79 %

Rationale: "the original output increases by 10 % and then 25 % . total % change = a + b + ab / 100 total % change = 10 + 25 + 10 * 25 / 100 = 37.5 % now , you want to change it to 0 , so , 0 = 37.5 + x + 37.5 x / 100 x = - 37.5 ( 100 ) / 137.5 = 27 % approximately answer is d"
Answer: D