Eliminating Answer Choices in the Math Section

Here is one of those tricks to quickly eliminate answer choices from math questions without finishing all calculations for the problem. It involves returning to 5th or 6th grade math and just going through the options and crossing out those that simply don't fit due to basic arithmetic, once the problem is in its simplest form. Of course, it only works for a couple types of problems, that can be simplified into this form, but every bit helps.

pos x pos= positive
neg x neg= positive
post x neg= negative

even + even= even
odd + odd= even
even + off= odd

even x even= even
odd x odd= odd
even x odd= even

If these last two sets are forgotten, just knowing that the rules exist is helpful. Then you can plug in a couple numbers to figure out the rule.