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!
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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 Challenge Combinations/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 [...]
Combinations Practice Question of the Week #27 Answer
Here are the answer and explanation to yesterday’s practice question. Thanks for submitting all of your answers!
Combinations Practice Question of the Week #27
For this week’s practice question, there’s only one correct answer. Good luck, we’ll be posting the answer and explanation tomorrow! In how many ways can Ann, Bob, Chuck, Don and Ed be seated in a row such that Ann and Bob are not seated next to each other? 24 48 56 72 96 Update: Here’s [...]
Real-Life GRE Math: Foosball Combinations
Who says math doesn’t relate to real life? Here is a question that came up in our office just the other day: An office comprised of eight employees is planning to have a foosball game. A matchup consists of four players, split into pairs. If any employee can be paired up with any other employee, [...]
Combinations and Permutations Practice Questions and Video Explanations
As a continuation of my introduction to Combinations and Permutations, here are some practice problems to test the strategies I demonstrated. Also, I am trying out a new format. Instead of giving you practice problems and then writing out a half-page description for each one, I am simply going to give you the questions. But don’t [...]
