With the advent of the calculator on the GRE, some would say the days of knowing how to do mental math are obsolete. While you could rely on the calculator for the entire test, doing so may actually slow you down. Indeed a facility mental math will save you a lot of time, and may […]

# Archive | Estimation and Approximation (Ballparking)

## GRE Quantitative Comparison Tip #5 – Estimation with a Twist

Here’s the whole series of QC tips: Tip #1: Dealing with Variables Tip #2: Striving for Equality Tip #3: Logic over Algebra Tip #4: Comparing in Parts Tip #5: Estimation with a Twist In my last post, we solved the following question: A. The quantity in Column A is greater B. The quantity […]

## GRE Quantitative Comparison Tip #4 – Comparing in Parts

To set up today’s Quantitative Comparison (QC) strategy, please solve the following question: A. The quantity in Column A is greater B. The quantity in Column B is greater C. The two quantities are equal D. The relationship cannot be determined from the information given There are several different ways to solve this question. […]

## GRE Math Techniques – The Power of Estimation

Many of us, when we first see a math question, hone in on it with laser-like focus. We make sure we read all the relevant parts, and then work out a solution to the problem. Only then do we look at the answers. There is nothing inherently wrong with approaching a math problem this way; […]

## GRE Math Strategies Part V of VI: Estimation

Some GRE problems invite Estimation. In fact, if you find yourself immersed in irksome computations, you may want to consider estimating the answer, especially when the answer choices are numerically well spaced. Example #1: Which of the following is nearest to (A) 20 (B) 15 (C) 10 (D) 5 (E) 1 (E) is the correct […]