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“Chelsea – it’s time for a Kindle” Challenge Question

Try the question below. It is not as tough as some of the challenge questions on this blog. That said, see if you can solve in less than 1 minute. Good luck! Chelsea has a bookshelf consisting of ten classics: four Russian novels, three British novels, two French novels, and a German novel. If she [...]

GRE Multiple Answer Challenge Question: Astronauts

In most likelihood, you will only get one or two combinations/permutations questions per test. Typically, the questions are quite challenging. Knowing the standard formulas won’t be enough; you’ll also have to use logic, and a fair amount of grit. Below is a question that will really force you to think, and rely on that grit. [...]

GRE Math Multi-subject Challenge Question

Once in a while it is fun to take a concept in an official GRE question and run with it. The question below is inspired by a question from the 2nd edition Official Guide. That is not to say it is that similar; I have only extracted a couple of concepts from that problem. I’ve [...]

Breakdown of the Most Commonly Tested GRE Quant Concepts

The 2nd edition Official Guide has just been released. At the back of the book is a new test (GRE Practice Test 2). In general, the concept break down is not surprising, if you look at the concepts that pop up in Practice Test 1 (which is the same as the practice test in the [...]

GRE Counting and Probability: Practice Question of the Week #39

Here’s this week’s practice question– good luck, we’ll be posting the answer tomorrow! How many integers between and  are such that the sum of their digits is ? 190 210 211 230 231 Update: Answer/explanation post!

GRE Permutations: Practice Question of the Week #37 Answer

Here’s the answer to yesterday’s practice question, thanks for sending in all of your answers!   Video Explanation

GRE Permutations: Practice Question of the Week #37

Here’s this week’s practice question (regular multiple choice, just one answer), we’ll be posting the answer tomorrow. Good luck! A popular website requires users to create a password consisting of digits only. If no digit may be repeated and each password must be at least 9 digits long, how many passwords are possible? 9! + [...]

GRE Probability: Practice Question of the Week #33

Here’s this week’s practice question– regular multiple choice, just one correct answer. We’ll be posting the answer and explanation tomorrow, good luck! If points A and B are randomly placed on the circumference of a circle with radius 2, what is the probability that the length of chord AB is greater than 2? 1/4 1/3 [...]

The Difficulty of Context: Combinations and Permutations Questions

Over the last couple of months, I have covered a fair amount of GRE combinations and permutations questions on the blog. I’ve gone from the very basic to the very difficult (so difficult that they are more ‘fun problem’ than practical practice). Often, when you are stumped on a problem, it is not that the [...]

Three GRE Challenge Combinations and Permutations Problems

Over the last few weeks, I have gone through GRE combinations and permutations. My goal is to make this formidable concept less intimidating. If you’ve watched the videos and feel comfortable with the math, I would say continue practicing but do not worry too much about this problem type. You will probably see one, though [...]