One of the most common misconceptions on the GMAT is that you have to solve every question in about 2 minutes. This of course stems from the fact that you have 75 minutes to answer 37 quantitative questions (or ~2.03 minutes per question) and 75 minutes to answer 41 verbal questions (or ~1.83 minutes per question). Both figures can be approximated to roughly two minutes per question on average; however, this does not mean that every question will take you 2 minutes to solve.

If you’ve been reading (my) GMAT blogs, you’ve undoubtedly come up against questions that would take over 3 minutes to solve for almost anyone. How can an exam with a strict average like the GMAT give you questions that can’t reasonably solved in less than 3 minutes? Unsurprisingly, it’s because some questions can be solved in less than 1 minute. As long as things average out to two minutes (or less), you’re golden.

Let’s consider two simple examples. If I took the set {2, 2, 2, 2, 2}, then the average would clearly be 2. This is achieved by taking the sum of all the numbers and dividing by the number of terms. Now if I took the set {½, ½, 3, 3, 3), then the average would still be 2! (exclamation mark, not factorial, although both work). While both numbers have the same average, the standard deviation (dispersion around the mean) is very different for the two sets. Simply put, if you can solve some questions in 30 seconds, then you have extra time for other, longer questions.

Earning some extra time by correctly answering questions quickly can be an invaluable tool in order to finish all the questions on this exam. I’d like to focus on a concept that gets asked relatively frequently on the GMAT that can be solved in 30 seconds or less if you understand the concept:

*256 teams play in a state soccer tournament. A team is eliminated from the tournament after one loss. In the first round, all 256 teams play one game. If a team wins, it advances to the next round, where it plays another winning team. This process repeats itself until only one team is left, having advanced through each round without losing. How many games are played in the tournament?*

Many sports buffs will recognize this set up as a single-elimination tournament. This format is used in football, soccer, Olympic sports and myriad other competitions when time is of the essence (so not baseball). 256 is a large, unwieldy number, so let’s unlock the concept of this question by using a smaller similar example: The upcoming World Cup. (I’m taking the long bet on Australia)

Once the initial groupings reduce to 16 teams in the elimination round, two teams will face each other and one will lose and therefore be eliminated. Thus the 16 teams will play 8 games, eliminating 8 countries and allowing the other 8 passage through to the next round. In the next round, 4 more games will occur pitting one team against another, leaving 4 teams standing after 12 total games. The 2 semi-finals will then whittle the teams down to 2 finalists after 14 total games. The final game will be played and leave only 1 country to claim the championship, as well as bringing the total number of games played to 15. Thus we need 15 games to bring 16 teams down to 1.

The executive summary of the paragraph above is simply that it will take n – 1 games to execute a single-elimination tournament. If there are 16 teams, you need 15 games. Had there been 32 teams, they would have played 31 games to crown a champion. You’ll also notice that many times the number of teams competing is a power of 2, as this set up allows for a smooth tournament where every team plays the same number of games. The same principle applies if you have, say, 21 teams as well. It would still take 20 games to get one victor.

Therefore, regardless of the number of teams participating in a single-elimination tournament, every game always eliminates one team, and therefore you always need n – 1 games to crown a champion. Once you recognize that the question is asking about single-elimination tournaments, you don’t have to do anything other than subtract 1 from the number of teams and the question is done. Even if you double check the question before submitting next, you can solve these questions in 30 seconds, freeing up extra time for more challenging questions. If you understand the concept, some GMAT questions can be solved in the time it takes to sit through a television commercial. So don’t turn a simple question into an infomercial. (where’s Billy Mays when you need him).

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*Ron Awad is a GMAT instructor for Veritas Prep based in Montreal, bringing you weekly advice for success on your exam. After graduating from McGill and receiving his MBA from Concordia, Ron started teaching GMAT prep and his Veritas Prep students have given him rave reviews ever since.*