by Focus Tutoring | Mar 2, 2021 | Combinatorics, GMAT, Quant

By: Rich Zwelling, Apex GMAT Instructor Date: 2nd March, 2021 So far, we’ve covered the basics of GMAT combinatorics, the difference between permutations and combinations, some basic permutation and combination math, and permutations with repeat elements. Now, we’ll...
by Focus Tutoring | Feb 25, 2021 | Combinatorics, GMAT, Probability, Quant

As promised in the last post, today we’ll discuss what happens when we have a PERMUTATIONS situation with repeat elements. What does this mean exactly? Well, let’s return to the basic example in our intro post on GMAT combinatorics: If we have five distinct paintings,...
by Focus Tutoring | Feb 23, 2021 | Combinatorics, GMAT, Quant

Last time, we looked at the following GMAT combinatorics practice problem, which gives itself away as a PERMUTATION problem because it’s concerned with “orderings,” and thus we care about the order in which items appear: At a cheese tasting, a chef is to present some...
by Focus Tutoring | Feb 18, 2021 | Combinatorics, GMAT, Quant

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,...
by Focus Tutoring | Feb 11, 2021 | Combinatorics, GMAT, Quant

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...