Did you know that Quantitative Comparison question account for half of the marks on the GRE’s Quantitative section? Here are some tips to help you through the challenge.
- Never do more work than needed. The questions simply ask you to compare quantities; you do not need to know by how much one is bigger (or smaller).
- Visual estimates are not enough. Looks can be deceiving so ensure all of your conclusions are based on mathematical calculations and data from the question.
- When in doubt, manipulate the data. You may be able to combine numbers or other terms, do some factoring, or restate in equation in a slightly different form. Remember, if expressions contain the same term, you can remove that term by adding or subtracting it from both quantities.
- When manipulating data, only multiply or divide across columns when the quantity you’re working with is positive. Multiplying or dividing two unequal terms by a negative value changes the inequality; and you’ll have manipulated the data into the wrong answer.
- Check your answers with simple math – if it’s possible. There’s no sense in analyzing a problem entirely in the abstract if it only takes a few seconds to scratch some numbers down on paper. Plus, putting your though process to paper helps you see if you’re making a mistake along the way.
- Don’t do too much math. None of these questions should require involved calculations – that is not the point of this section. If you find yourself crunching complex equations, you’ve likely missed something in the question. Put down the pencil and reread it!
- Never choose the relationship cannot be determined from the information given if a comparison does not involve variables or figures. If the comparison involves numbers only, you’ll always be able to calculate specific numerical values for both expressions, so the last (fourth) answer choice cannot possibly be the correct one!
- Consider all the possibilities for unknowns. Unless the centered information restricts their value, consider positive and negative values, as well as fractions and the numbers zero (0) and 1. Comparisons often depend on which sort of number is used so in these cases, you should strongly consider the relationship cannot be determined from the information given.
Time for you put these tips to the test.