GRE Answer Choice Tricks, Part 4
The test makers like for there to be as few negative signs as possible in their fractions. Take a look at this one:
This would never be the correct answer choice, since there’s a way to cut a negative sign. If you ever get a fraction with variables as your answer and don’t see it in the answer choices, don’t panic. Chances are, you just need to fiddle with the negative signs a bit. Multiply the top and bottom of the fraction by -1:
This is good to know in general: multiplying (a - b) by a negative sign causes the variables to flip around and make (b - a). You can tweak the order of terms around a minus sign to your heart’s content with negative multiplication.
If you’ve encountered other tricky answer choice situations, let us know in the comments!