Here’s a simple solution to the classic “For a certain race, 3 teams were allowed to enter 3 members each” GMAT question. First, let’s look at the question text so you know what we’re talking about: For a certain race, 3 teams were allowed to enter 3 members each. A team earned 6 – n … Read More
GMAT Combinatorics Questions: Permutations vs. Combinations (plus Shorthand!) As noted above, this is simply a clipped factorial. Let’s take the case from above and modify it slightly. Three paintings, from a group of seven total paintings, are chosen to be hung on a wall. In how many ways can these three paintings be arranged? So: … Read More
GMAT Combinatorics: an Introduction Ever wonder why GMAT Permutations and Combinations seem to hard to learn? There’s no good reason–that’s just because they tend to be explained in a terrible way. It’s time for us to fix that! At the risk of blowing all the secrets too early, let’s do this at the beginning. If … Read More