“Many a true word is said in jest.”—I don’t know, but I heard it from my mother.

Once upon a time in America, when I was a boy, my father, an engineer, said to me, “You can make numbers do anything you want them to do.”  This was the beginning of my cynicism.  But never mind that.  My father was fluent in four languages: English, German, French, and Algebra.  My father was also a very honest man.  His comment relied on the fact that most people can’t read Algebra—he just let people fool themselves.  Teaching GMAT classes, I combat the fact that many people can’t read Algebra.  Like my father, the GMAT exploits that weakness and lets—nay, encourages—people to fool themselves.  Thus, for many, preparing for the quantitative portion of the GMAT is akin to studying a foreign language.  (I know that even many native speakers feel that preparing for the verbal portion of the GMAT is also akin to studying a foreign language.  But that’s a different topic.)  In any case, you want to make your Algebra as fluent as your French. . .yes, for most of you, that was one of those jokes.

I know that some of you disagreed with the above and feel that the problem is an inability to understand math.  But that’s not true, at least on the level necessary to succeed on the GMAT.  If you really didn’t have enough synapses, they wouldn’t let you out without a keeper—because you couldn’t tip, or comparison shop, or count your change.  It’s a literacy problem.  Think about the math units in the course.  Truthfully, the first one is often a death march.  By the end, as country folk say, I often feel like I’m whipping dead horses.  On the other hand, the lesson concerning probability and combinations, putatively a more advanced topic, usually goes really well.  Why?  Because folks can read the words and understand their meaning.  Conversely, folks just stare at the algebraic symbols as if they were hieroglyphics.  The problem is that putting a Rosetta Stone in the book bag would make it weigh too much. . .kidding.  But if you can’t read the hieroglyphics, the mummy will get you—just like in the movies.

It really is a literacy issue and should be approached in that fashion.  You still don’t believe me?  You want specific examples?  I got examples, a pro and a con.  On the affirmative side, I once worked one on one with a man who came to me because his math was in shreds.  Because he couldn’t read what the symbols were saying.  Partly because his mother had once said, “Your sister is the one that’s good at math.”  As far as the GMAT is concerned, she was wrong, and so was your mother, if she said that.  Anyway, one day I gave him a high level Data Sufficiency word problem concerning average daily balances on a credit card.  He looked at it for about 30 seconds, and he didn’t write anything on his scrap paper.  Then he turned to me and said the answer was blah blah.  And he was right.  I looked at him and said, “How did you do that?  You’re not that good.”  (Yes, this is also an example of how mean I am to private students.)  But—and here’s the real punch line—he said, “It was about debt; I understood what the words meant.”  And there you go.  As a by the way, he worked very hard, became competent although not brilliant quantitatively, scored 710—97%V, 72%Q*—and went to Kellogg.

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Exciting news for iPhone users! Our new Pocket GMAT app is now available for FREE in the iTunes App store. Containing over 350 GMAT quant flash cards, the app uses an adaptive algorithm developed by Manhattan Prep instructors to help you target cards you most need help with. Allowing you to work on your GMAT quant anywhere and at any time, the Pocket GMAT app is sure to be an indispensable tool for iPhone users.

Pocket GMAT is available for the iPhone and iPod Touch and was built with our friends at Learningpod, who are focused on making great practice and assessment questions free for everyone. In addition to the adaptive algorithm, there is also a sequential practice mode that lets you flip through the cards however you want. You also have the ability to enter a Target Date to keep you on pace and track your progress. The flash cards are organized into “KeyRings” by topic and include algebra, number properties, word problems, geometry, fractions, decimals, and percents.

You can download the app via the iTunes App store, here.

We invite you to test your GMAT knowledge for a chance to win! Each week, we will post a new Challenge Problem for you to attempt. If you submit the correct answer, you will be entered into that week’s drawing for a free Manhattan GMAT Prep item. Tell your friends to get out their scrap paper and start solving!
Here is this week’s problem:

At 8am on Thursday, two workers, A and B, each start working independently to build identical decorative lamps. Worker A completes her lamp at 5pm on Friday, while Worker B completes her lamp sometime during the morning on Friday. If both workers adhere to working hours of 8am to 12pm and 1pm to 5pm each day, at which of the following times might the two workers have completed a single lamp had they worked together at their respective constant rates?

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We invite you to test your GMAT knowledge for a chance to win! Each week, we will post a new Challenge Problem for you to attempt. If you submit the correct answer, you will be entered into that week’s drawing for a free Manhattan GMAT Prep item. Tell your friends to get out their scrap paper and start solving!
Here is this week’s problem:

If three different integers are selected at random from the integers 1 through 8, what is the probability that the three selected integers can be the side lengths of a triangle?

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We invite you to test your GMAT knowledge for a chance to win! Each week, we will post a new Challenge Problem for you to attempt. If you submit the correct answer, you will be entered into that week’s drawing for a free Manhattan GMAT Prep item. Tell your friends to get out their scrap paper and start solving!
Here is this week’s problem:

In the figure above, ABC is a right triangle with AC as its hypotenuse, and PQRS is a square. What is the area of the square?

(1) AC is 70 units long.

(2) The product of the length of AS and the length of RC is 396.

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We invite you to test your GMAT knowledge for a chance to win! Each week, we will post a new Challenge Problem for you to attempt. If you submit the correct answer, you will be entered into that week’s drawing for a free Manhattan GMAT Prep item. Tell your friends to get out their scrap paper and start solving!
Here is this week’s problem:

For how many unique pairs of nonnegative integers {a, b} is the equation a² – b² = 225 true?

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In honor of the final season of Breaking Bad, we decided to put together our ultimate Breaking Bad GMAT quiz. Those of you who fall in the overlapping section of the “Breaking Bad Fan” “GMAT student” Venn diagram should test your skills below… yo!

1. Data Sufficiency

Does x+4 = Walter White?

(1) x+4 is the danger
(2) x+4 is the one who knocks

A. Statement (1) ALONE is sufficient, but statement (2) ALONE is not sufficient
B. Statement (2) ALONE is sufficient, but statement (1) ALONE is not sufficient
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient
D. EACH statement ALONE is sufficient
E. Statement (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data are needed

2. Discrete Quant

The front portion of Walter White’s Roof is a 7 ‘ by 15’ rectangle. If the diameter of a pizza is 22”, what is the approximate area of the shaded region of this diagram?

A. 13,600 inches sq.
B. 14,740 inches sq.
C. 15,120 inches sq.
D. 15,500 inches sq.
E. 16,640 inches sq.

3. Critical Reasoning

Today, Walter White will cook 100 pounds of methamphetamine.

This argument is flawed primarily because:

A. Cooking methamphetamine presents a moral dilemma for Walter White.
B. Walter White has to prioritize the needs of his wife and children and be a better father.
C. Walter has already paid for his cancer treatment and no longer needs to cook methamphetamine.
D. There is a fly in the laboratory.
E. He was told not to cook that day and is obeying his instructions.

4. Critical Reasoning

Hank’s collection of rocks includes over 400 different items. Hank’s rock collection is clearly the most impressive in New Mexico.

This argument is flawed primarily because:

A. Rock collections are not judged by the total number of rocks but by the rarity of each item included.
B. Rock collections are not impressive to anyone.
C. Hank’s rock collection is a metaphor and therefore cannot be judged against other rock collections.
D. Hank’s wife stole most of the rocks and it is therefore ineligible for any superlatives.
E. They aren’t rocks, they are minerals.

5. Discrete Quant

Walter Junior eats 3 eggs for breakfast every morning. Given that Walter Junior never misses breakfast, how many eggs does Walter Junior consume in March?

A. 60
B. 74
C. 82
D. 93
E. 107

Answers are after the jump…

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We invite you to test your GMAT knowledge for a chance to win! Each week, we will post a new Challenge Problem for you to attempt. If you submit the correct answer, you will be entered into that week’s drawing for a free Manhattan GMAT Prep item. Tell your friends to get out their scrap paper and start solving!
Here is this week’s problem:

A coin purse contains 13 coins, each worth 1, 5, 10, or 25 cents; the total value of the coins is 150 cents. How many 10-cent coins are in the purse?

(1) The 13 coins can be divided among five separate envelopes so that each envelope contains the same total monetary value.

(2) The 13 coins can be divided among six separate envelopes so that each envelope contains the same total monetary value.

A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.

B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.

C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

D. EACH statement ALONE is sufficient.

E. Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data are needed.

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Some people really like ratio problems while others struggle with these. What do you think?

Let’s talk about a go-to solution method when handling a problem of this type. Try this GMATPrep problem:

* ” The number of stamps that Kaye and Alberto had were in the ratio 5 : 3, respectively. After Kaye gave Alberto 10 of her stamps, the ratio of the number Kaye had to the number Alberto had was 7 : 5. As a result of this gift, Kaye had how many more stamps than Alberto?

 

“(A) 20

“(B) 30

“(C) 40

“(D) 60

“(E) 90”

My very first thought as I read this problem: I have to be very careful with my work here, because it would be really easy to solve for the wrong thing (and, of course, that wrong answer will probably be among the answer choices).

As an aside, I’ve found that this attitude is one of the biggest differences between someone who has the potential to hit a top score on quant and someone who won’t make it. When you see something and you think, “I know how to do this!” the top test-taker is going to go in The Zone and pay even more attention to detail, thinking “I am going to be really careful not to make a mistake on this one!” Someone who isn’t going to hit a tip-top score will instead start to coast a little mentally, thinking, “Yeah, I’ve already got this.” Even worse, someone might think, “I can speed up on this one since I know how to do it.”

No! Don’t speed up! You don’t necessarily have to take the full 2 minutes, but don’t go any faster than you’d normally go. Don’t increase the chances that you make a careless mistake!

Okay, let’s solve this thing.

First, make very clear on your scrap paper what you want: Kaye NEW minus Alberto NEW. Not just Kaye (new or old). Not Kaye’s original number of stamps minus Alberto’s original number.

Skip a few lines and write this on the scrap paper and put a big circle around it: K_n – A_n. Do the actual work up above this text and, when you’re done, you’ll “run into” the reminder that you want Kaye NEW minus Alberto NEW.

Also, make sure you organize your work carefully as you go so that you know which portions represent the original numbers versus the new ones.

Let’s see.

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We invite you to test your GMAT knowledge for a chance to win! Each week, we will post a new Challenge Problem for you to attempt. If you submit the correct answer, you will be entered into that week’s drawing for a free Manhattan GMAT Prep item. Tell your friends to get out their scrap paper and start solving!
Here is this week’s problem:

In the xy-coordinate plane, line L passes through the points (b, a) and (c, 0), and line Mpasses through the point (a, b) and the origin, where a, b, and c are different nonzero integers.  Do lines L and M intersect?

(1) 

(2) c < 0

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