What are combinations? Conceptually, the combinations task is easy to understand: it’s about the number of ways to select a subgroup from a whole group. As in the permutations task, the whole group is notated as n, and the subgroup is notated as r. The standard...
By: Apex GMAT Contributor: Svetozara Saykova Date: 24th June 2021 Combinatorics can seem like one of the most difficult types of questions to come across on the GMAT. Luckily there are not many of them within the exam. Still these questions make up the top level of...
By: Rich Zwelling, Apex GMAT Instructor Date: 16th March, 2021 Now, we’d like to take a look at an Official GMAT Probability problem to pull everything together. The following is a good example for two reasons: 1. It illustrates a quirky case that is difficult more...
Review of Example From Last Post Last time, when we started our discussion of GMAT Combinatorics, we gave a brief example of GMAT permutations in which we had five paintings and asked how many arrangements could be made on a wall with those paintings. As it turns out,...
GMAT Combinatorics. It’s a phrase that’s stricken fear in the hearts of many of my students. And it makes sense because so few of us are taught anything about it growing up. But the good news is that, despite the scary title, what you need to know for GMAT...
