While the exam does not provide explanations for answers, you may find it beneficial to reason in your head why your answer is wrong and the correct answer is indeed correct. I found this method to be particularly helpful with data sufficiency questions. When you think through the answer to a problem and really understand why your answer is wrong and why another is correct, you can more easily remember how to do the type of problem correctly and even learn to recognize when you are at risk of repeating the erroneous thinking. However, if you are unable to figure out why a particular answer is correct I'm sure you could ask the members of the forum as was stated above.
Best of luck.
ajk
