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# Archive | Exponents

## Magoosh Brain Twister: The Smallest Big Change – Explanation

Alright Magooshers, let’s see how you fared on this week’s Brain Twister!   Question Lowering which of the following numbers by one will result in the least decrease of n? 17 19 23 29 31   Answer and Explanation The GRE likes to test your ability to reason with numbers. Can you see general patterns, […]

## Magoosh Brain Twister: The Smallest Big Change

Welcome back, brave Magooshers! Ready to tackle another brain twisting math challenge? Here we go. Lowering which of the following numbers by one will result in the least decrease of n? 17 19 23 29 31   Don’t forget to come back on Thursday for the answer and explanation!

## Magoosh Brain Twister: Zeroing In on the Answer

This week’s Brain Twister is a numeric entry question. Ready to give it a go?   …. How many zeroes does ‘n’ contain at the end of the number (to the right of the last non-zero digit)? Numeric Entry [________________]   Wondering how you fared? Check back on Thursday for the answer and explanation! 🙂 […]

## GRE Math – Exponent Challenge

A relatively common exponent question on the GRE will ask you to figure out the units digit of some number raised to an exponent, which usually results in a number roughly equivalent to the number of grains of sand in the Sahara, and thus out of reach of the GRE calculator. Take a look at […]

## GRE Quant: The Difference of Squares

If you’ve been studying GRE for some time, you’ve very likely encountered the following: . You may, however, only seen the following equation in the context of algebra. Nevertheless, the formula above applies to number properties. Let’s take a look. While you may be tempted to make a mad dash at it, calculating each of […]

## GRE Exponents: Practice Question Set

Each of the math questions below is directly inspired by a question in the on-line Revised GRE test. I’ve provided an easier version of the question (#1) and a more difficult version of the question (#2). My recommendation is to try the easier version first. Then, if you answer it correctly, click on the link, […]

## GRE Math Basics: Quick Tips

Prime numbers 2 is the smallest prime number 2 is the only prime even number 1 is not a prime 3, 5, 7 are the only three consecutive odd integers that are each a prime.   Digits In the integer 5,432, 5 is the thousands digit, 4 is the hundreds digit, 3 is the tens […]

## GRE Math Multiple Choice Practice Question of the Week #23

This week’s practice question is a regular multiple choice problem, so there’s only one right answer– good luck! We’ll be posting the answer tomorrow.   Which of the following equations is true for all positive values of x and y?   Update: Here’s the answer/explanation post!

## GRE Math Video Lessons: Exponents

Exponents are troublesome; fortunately, they do not need to be. What I plan to do in this series is show you the basics, so that you can move confidently through the intermediate level, and even the advanced level. I’ve created three lessons, corresponding to basic, medium, and advanced. You can watch them here: Exponents Level 1 […]

## Numeric Entry Practice Question of the Week #21 Answer

Here are the answer and explanation to yesterday’s practice question.  Thanks for submitting your answers!     Video Explanation: