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 10%. By approximately what percent would the output now have to be decreased in order to restore the original output? Choose the correct choice from the following answers.
A) 20 %  B) 24 %  C) 30 %  D) 32 %  E) 17 %

Rationale: "the original output increases by 10 % and then 10 % . total % change = a + b + ab / 100 total % change = 10 + 10 + 10 * 10 / 100 = 21 % now , you want to change it to 0 , so , 0 = 21 + x + 21 x / 100 x = - 21 ( 100 ) / 121 = 17 % approximately answer is e"
Answer: E