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...
Permutations are a type of combinatorics task that is often tested on the GMAT. In a permutations question, you are asked to find the number of ways to order a group of elements. The order of the elements matters in permutations questions, so the number of possible...
What is an Ordering Task? Ordering tasks are a common type of question on the GMAT. In an ordering task, you are asked to determine the number of ways to order a set of objects. The number of ways to order n different objects is n!, or n factorial. The best way to...
Every combinatorics question on the GMAT involves one or more of three fundamental combinatorics tasks: ordering, permutations, and combinations. This article will introduce the three tasks, and each of the three following articles will explain a task intuitively to...
Welcome back to our series on GMAT quant rate problems. In this final article, we’ll explore problems that have algebraic expressions as answer choices. You have a few options whenever you encounter one of these problems, but this article will focus on solving them by...