I’ve never been a big fan of the phrase “Combinations and Permutations.” It suggests that all counting questions can be solved using either combinations or permutations, when this is not so. Compounding the problem is an infamous rule that...

Most GMAT students don’t spend enough time considering the mindset they’ll need on test day. In my very first article, I suggested that the simple act of smiling can increase your performance. In this article, we’ll go a little deeper and...

To set up this article, please consider a forum post from some fictitious wrestling forum:
The state wrestling tournament is 1 month away, and I want to win the 184-pound weight class. To lose enough weight to qualify for that weight class...

Welcome to part three of a three-part series on common mistakes that students make when answering GMAT Data Sufficiency questions.
In this article, we’ll examine two mistakes related to equations.
Mistake #1 – Assuming that 2 equations...

Welcome to part two of a three-part series on common mistakes that students make when answering GMAT Data Sufficiency questions.
In this article, we’ll examine mistakes related to assumptions about number classifications.
Mistake #1 -...

Doing well on the GMAT is a key part of your MBA admissions. It’s split into four parts: analytical writing (30 minutes), integrated reasoning (30 minutes), quantitative (75 minutes) and verbal (75 minutes). Your chances of getting into...

Welcome to part one of a three-part series on common mistakes that GMAT students make when answering Data Sufficiency questions.
In this article, we’ll examine two kinds of mistakes that GMAT newcomers often make, and in the next two...

At some point during your high school years, your math teacher may have presented you with the following “proof” that 1 + 1 = 1. See if you can spot the problem.
1) Begin with the premise that b = c
2) Multiply both sides by b to get: b^2...

To set up this article, please try the following test:
For the next 10 seconds, do NOT think about a bear wearing a dress while riding a unicycle into a pool filled with Superbowl rings.
How did you do? If you passed that test, the next...

Try this one:
What is the units digit of 13^35?
A) 1
B) 3
C) 5
D) 7
E) 9
Let’s begin by looking for a pattern as we increase the exponent.
13^1 = 13 (units digit is 3)
13^2 = 169 (units digit is 9)
13^3 = 2197 (units digit is 7)
Aside: As...