First of all, try these challenging GMAT Problem Solving practice problems without a calculator. (A) 2 (B) 3 (C) 4 (D) 5 (E) 6 2) In the month of August, Pentheus Corporation made $200,000 in profit. Pentheus made 6% of that profit on the second Wednesday of August. If the profits that day were approximately […]

# Archive | Basics

## GMAT Quant: Arithmetic with Inequalities

Here are four GMAT Data Sufficiency questions involving inequalities. Full solutions will come at the end of this article. The arithmetic of equations: a review First of all, let’s review what should be more familiar — the arithmetic of equations. Suppose A = B and P = Q. The soundbyte is: you can combine […]

## GMAT Quantitative: Ratio and Proportions

First, a bank of eight practice problems 1) A certain zoo has mammal and reptiles and birds, and no other animals. The ratio of mammals to reptiles to birds is 11: 8:5. How many birds are in the zoo? Statement (1): there are twelve more mammals in the zoo than there are reptiles Statement (2): […]

## GMAT Quant: Mathematical Grouping Symbols

Many folks remember Order of Operations by means of the mnemonic PEMDAS. Just for review, PEMDAS is a quick way to remember the following order of mathematical prioritization: Priority #1: P = Parentheses Priority #2: E = Exponents Priority #3: MD = Multiplication & Division Priority #4: AS = Addition and Subtraction A few things […]

## Mathematical Thinking on the GMAT

What does the GMAT Quantitative section test? Math, of course. As tautological as that may seem, there is a very subtle point here. What exactly is math? Mathematics Strange as it may seem, there is no generally accepted formal definition of the word mathematics. Most of the dictionary definitions, for example, cover the more […]

## GMAT Number Properties

The single most-tested topic on the GMAT Quantitative Section is something called “Number Properties.” In a way, this statement, while absolutely true, is a bit deceptive. It’s like saying the biggest category at a particular zoo is mammals: even if that is completely true, that statement alone doesn’t give us a particular clear idea of […]

## GMAT Math: Probability Rules

First, some practice questions. The scenario below is relevant to questions #1-#3. There are two sets of letters, and you are going to pick exactly one letter from each set. Set #1 = {A, B, C, D, E} Set #2 = {K, L, M, N, O, P} 1) What is the probability of picking a […]

## GMAT Math: One is NOT a Prime Number

Fact: according to all mathematical definitions, the number 1 is not a prime number Primes One definition of a prime number is: any number that has only two positive integer factors—itself and 1. The following are valid prime numbers. 2, 3, 5, 7, 11, 13, 17, 19, 23, 29 …. It is very good […]

## Doubling and Halving Trick for GMAT Math

Learn one of the handiest tricks for math without a calculator! Without a calculator, what is 1. 35 x 12? 2. 150 x 36? 3. 125 x 84? On the GMAT, you don’t get a calculator. With the doubling and halving trick, all of these become much easier. Thinking about multiplication Every positive […]

## GMAT Math: The Many Meanings of Minus

First of all, for warm-up, a practice Data Sufficiency question. The symbol What does this symbol mean in math? Technically, this symbol, typographically a dash, has three different meanings in mathematics, viz.: a) a subtraction sign b) a negative sign c) an opposite sign The subtraction sign When the dash appears between two terms […]