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 20%. By approximately what percent would the output now have to be decreased in order to restore the original output?
This question is possible in the real gmat ?? what is the level ?? I guess sub 600 but for me is even more less. However, it is classified as upper medium level
Assume that the output is 100. After the first increase, it is 110. 20% increase of 110 is 22, so the new output is 132 (10% of 110 is 11, so 20% is 2*11=22).
To restore the initial output of 100, we need to reduce the new output 132 by 32. This represents 32/132, which is close but a little bit less than to 32/128 =25%.
Maybe the statistics show that people don't like so much % questions and/or they are not so good at them.
PhD in Applied Mathematics
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