We’ve just released our first eBook, and it’s on Integrated Reasoning!

It includes:

• An overview of the section as a whole, including scoring
• Overviews and strategies of/for each question type
• Practice questions of each question type
• Recommendations for what and how to study to do your best on this new section!

And it’s free! So feel free to print it out, share with friends, and use it on the go to read up on how to conquer Integrated Reasoning on the new GMAT, starting in June.

If you have any suggestions, feedback, or questions about this eBook, let us know by leaving a comment below.  We’d also love to hear any suggestions for the topic of our next eBook (idiom lists? math formulas?), so let us know those as well!

Click here to download the eBook.

Enjoy!

That Barron’s is such a travesty in GMAT is a surprise, considering that it does a decent to good job of presenting a host of other tests. But if you are reading this post, you do not care about the SAT. You care about the GMAT. And if you want to be prepared for the mix of artistically crafted questions—painstakingly wrought to provide for optimum trickiness—the last thing you want to do is any of the practice questions that the Barron’s guide tries to pass off as GMAT questions.

Tips and Strategies

Some of the material in here is enlightening, but isn’t necessarily relevant to GMAT. The Critical Reasoning section delves into areas of logic not touched on the GMAT. The Fallacies of Relevance are totally irrelevant. Ad Hominem attacks on the GMAT? And teaching anyone the word Amphiboly, while omitting even the basic Critical Reasoning question types is criminal.

The Reading Comprehension sections also omits the usual helpful strategies and focuses more on reading comprehension techniques that would helpful for high school students looking to take a state test.

Math strategies tend to be basic. That makes sense, given that many of the practice questions are quite basic.

Accuracy of Questions

If you want actual GMAT questions, you may be hard-pressed to find a single one in this book. Barron’s is so consistently oblivious of how to write a GMAT question, I wonder if they ever cracked open the Official Guide. More likely they followed some rubric for writing standardized test questions that they assumed would apply to one of the most grueling graduate exams.

Math

The math section is slightly better than the Verbal. Some helpful strategies and exercises—at least for those who haven’t seen the test in years. For more advanced tips and practice, look elsewhere. While I do like that they rate problems with a one to three star rating (1 for the easy; 3 for the difficult).

What is saliently absent are questions with the complexity of GMAT questions. And I do not just mean dense word problems (though those are also missing), but questions suggesting a diabolically clever mind was behind them. In other words, Barron’s provides a bunch of relatively straightforward questions that won’t help you deal with the deviousness of real Data Sufficiency and Problem Solving questions.

Verbal

Sentence Corrections

The first time I flipped open the Barron’s GMAT guide, I thought I was looking at the wrong book. Had I opened a TOEFL book? Nope. Barron’s apparently thinks that the GMAT tests very basic grammar, eschews convoluted sentence structure, and tends to underline only a few words. I feel sorry for those who bought this book, only to be utterly shocked test day.

Critical Reasoning

Critical Questions are difficult to write. Very few publishers do a good job. Barron’s clearly isn’t one of them. Passages are relatively straightforward and will not prepare you for the rigors of the GMAT.

Reading Comprehension

The passages are an inconsistent batch. Some have that GMAT-ish feel to them, presenting opposing theories on some laughably arcane topic. Most, however, are just dense and dry, but do not necessarily put forth a theory on a topic. The worst feel that they were plucked from an Encyclopedia.

The questions are definitely more consistent. Unfortunately, they are consistently bad. I’m reminded more of state entrance exams or poorly written SAT material.

Questions such as: The best possible title for the passage is are not even found on the GMAT. I really cannot say with any confidence that the authors of this book even bothered to flip through The Official Guide. If they did, they clearly weren’t inspired and seemed more intent on writing a dubbed down, duller version of the GMAT.

Stay away from Barron’s. There is nothing in this book that will help anyone who is serious about doing well on the GMAT.

Grade: F

Fact: All lines with slopes of 1 make 45º angles with both the x- and y-axes.

Conversely, if a line makes a 45º angles with either the x- of y-axes, you know immediately its slope must be . This first fact is true, not only for y = x and y = –x, for all lines of the form y = mx + b in which m equals either 1 or –1.  If the slope is anything other than , you would need trigonometry to figure out the angles, and that’s beyond the scope of GMAT math.  The GMAT could expect you to know this one fact about these special lines, especially on Data Sufficiency.

As a Mirror

Fact: Suppose we treat the line y = x as a mirror line.   If you take any point (a, b) in the coordinate plane, and reflect it over the line y = x, the result is (b, a).  It reverses the x- and y-coordinates!

The corollary of this is that if we compare any two points with reversed coordinates, say (2, 7) and (7, 2), we automatically know that each is the image of the other by reflection over the line y = x.  Add now the geometry fact that a mirror line is the set of all points equidistant from the original point and its image.  This means that the midpoint of the segment connect (2, 7) and (7, 2) must lie on the line y = x.  In fact, any point on the line y = x will be equidistant from both (2, 7) and (7, 2).  Without doing a single calculation, we know, for example, that the triangle formed by, say, (2, 7) and (7, 2) and (8, 8 ) must be an isosceles triangle.

When we reflex over the line y = –x, the coordinate are reversed and made their opposite sign: e.g. (2, 7) reflect to (–7, –2), and (–5, 3) reflects to (–3, 5).  The other conclusions, about equidistance, remain the same.

As a Boundary

Fact: Any point (x, y) in the coordinate plane that is above the line y = x has the property that y > x.  Any point (x, y) in the coordinate plane that is below the line y = x has the property that y < x.

Can you sense the veritable cornucopia of Data Sufficiency questions that could arise from this fact?  If you every see a question about the coordinate plane asking whether y > x or y < x, chances are very good that the line y = x is hidden somewhere in the question.

Practice Questions

1) Is the slope of Line 1 positive?

Statement #1: The angle between Line 1 and Line 2 is 40º.
Statement #2: Line 2 has a slope of 1.

1. Statement 1 alone is sufficient but statement 2 alone is not sufficient to answer the question asked.
2. Statement 2 alone is sufficient but statement 1 alone is not sufficient to answer the question asked.
3. Both statements 1 and 2 together are sufficient to answer the question but neither statement is sufficient alone.
4. Each statement alone is sufficient to answer the question.
5. Statements 1 and 2 are not sufficient to answer the question asked and additional data is needed to answer the statements.

2) Point (P, Q) is in the coordinate plane.  Is P > Q?

Statement #1: P is positive.
Statement #2: Point (P, Q) above on the line y = x + 1.

1. Statement 1 alone is sufficient but statement 2 alone is not sufficient to answer the question asked.
2. Statement 2 alone is sufficient but statement 1 alone is not sufficient to answer the question asked.
3. Both statements 1 and 2 together are sufficient to answer the question but neither statement is sufficient alone.
4. Each statement alone is sufficient to answer the question.
5. Statements 1 and 2 are not sufficient to answer the question asked and additional data is needed to answer the statements.

3) A circle has a center at P = (–4, 4) and passes through the point (2, 3).  Through which of the following must the point also pass?

1. (1, 1)
2. (1, 7)
3. (–1, 9)
4. (–3, –2)
5. (–9, 1)

Practice Questions Explanations

1) A straightforward prompt.

Statement #1 is intriguing: it gives us a specific angle measure.  This is tantalizing, but unfortunately, it is only the angle between Line 1 and Line 2, and that angle could be oriented in any direction.  Therefore, we can draw no conclusion about the prompt from this statement alone.  Statement #1, by itself, is insufficient.

Statement #2 is also tantalizing, because it’s numerically specific.  But, unfortunately, this tells us a lot about Line 2 and zilch about Line one, so this statement is, by itself, is also insufficient.

Now, combine the statements.  From statement #2, we know Line 2 has a slope of 1, which means the angle between Line 2 and the positive x-axis is 45º.   We know, from statement #1, that Line #1 is 40º away from Line 2.  We don’t know which way, above or below Line 2.  If Line 1 is steeper than Line 2, it makes an angle of 45º + 40º = 85º with the positive x-axis.  If Line 1 is less steep than Line 2, it makes an angle of 45º – 40º = 5º with the positive x-axis.  Either way, its angle above the positive x-axis is between 0º and 90º, which means it has a positive slope.  The combined statements allow us to give a definitive answer to the prompt question.  Answer = C.

2) We see the x > y type question in the prompt, which makes us suspect that the line y = x will play an important part at some point.

Statement #1 just tells us P is positive, nothing else.  The point (P, Q) = (4, 2) has the property that P > Q, but the point (P, Q) = (4, 5) has the property that P < Q.  Clearly, just knowing P is positive does nothing to help us figure out whether P > Q.  Statement #1, by itself, is wildly insufficient.

Statement #2 is intriguing.  It discusses not the line y = x but the line y = x + 1.  What is the relationship of those two lines?  First of all, they are parallel: they have the same slope.  The line y = x has a y-intercept of zero (it goes through the origin), while the line y = x + 1 has a y-intercept of 1.  This means: any point on the line y = x + 1 must be above the line y = x.  If (P, Q) is on y = x + 1, then it is above y = x, which automatically means Q > P.  We can give a definite “no” answer to the question.  By itself, Statement #2 is sufficient.  Answer = B.

3) For this problem, there’s a long tedious way to slog through the problem, and there’s a slick elegant method that gets to the answer in a lightning fast manner.

The long slogging approach — first, calculate the distance from (–4, 4) to (2, 3).  As it happens, that distance, the radius, equals .  Then, we have to calculate the distance from  (–4, 4) to each of the five answer choices, and find which one has also has a distance of   —- all without a calculator.

The slick elegant approach is as follows.  The point (–4, 4) is on the line y = –x, so it is equidistant from any point and that point’s reflection over the line y = –x.  The reflection of (2, 3) over the line y = –x is (–3, –2).  Since (–3, –2) is the same distance from (–4, 4) as is (2, 3), it must also be on the circle.  Answer = D.

Business education, teaching methodology, language and culture varies massively across Europe. Of course it’s a hugely diverse continent, with several hundred b-schools across divided between it’s 50 countries and 23 ‘official EU languages’ spoken (although others are also used).

Europe plays host to a quarter (23) of the top 100 business schools in the world (according the the FT MBA rankings) and is still held up in high esteem as a prestigious MBA destination. Europe also has the MBA Tournament (MBAT), started in 1991 it’s the largest sporting event for b-schools with 1,500 participants from fourteen business schools across Europe (hosted by HEC Paris)!

Here are some profiles of MBA students who’ve chosen to stay or travel to different parts of Mainland Europe to study. All of the people featured are active members of BusinessBecause.

France

Lara Gilman, MBA from INSEAD in Fontainebleu

An exciting job, business travel around the world, and a lot of responsibility: Lara Gilman seemed to have it all. But after four years in the same company, the 28-year-old from the US East Coast decided it was time for a new challenge, and enrolled for an MBA at INSEAD in Fontainebleau.

Gilman admits that getting an MBA from a US business school would have been the obvious choice, and she did apply to McDonough School of Business (Georgetown University) and to Haas at Berkeley. There is one area, however, in which American schools don’t match their European counterparts says Gilman: diversity. “At a US business school, 75 per cent of my classmates would have been American. At INSEAD they constitute only about 8 per cent.” She felt that working with people from different cultures, with diverse experiences and skill sets would be the perfect training for her dream career in a global transnational organization, says Gilman who obtained her first degree in French and urban studies.

Nina Fattahi, MBA from Grenoble Ecole de Management in Grenoble

Nina wanted to broaden her horizons and look for opportunities outside the US. Grenoble Ecole de Management was already familiar to her, and that’s where she turned for a heavy-weight MBA that would take her out of her comfort zone. She had spent a year abroad there during her first degree, a BSc in Finance and International Business from the University of Connecticut, so she knew what the School offered.

“Our class of 42 had 22 different nationalities. In a globalized world, this type of scenario is not uncommon and I wanted to be able to learn how to work with people from many different nations.” The Grenoble MBA also appealed to Nina in terms of its high international ranking and “attractive cost-to-value ratio”.

Italy

Monica Hornung Cattan, MBA from MIP Politecnico di Milano in Milan

Monica studied for her MBA at MIP Politecnico di Milano, Italy, and says that “in six years I have lived in five countries and seven cities”. She told us about how her MBA took her to work at the United Nations Economic Commission for Europe (UNECE).

Monica, 27, believes that MIP Politecnico di Milano is brilliant for the international exposure it offers and the Italian context it is so steeped in. “Italians have great creativity. In times of crisis creativity is glue. You need creativity to go through all the things that are happening in the world at the moment. And the MIP Politecnico di Milano MBA has the Italian particularities built into the programme therefore the course improves our capability to react.”

Spain

Michelle Lanspa, MBA at IE Business School in Madrid

IE Business School’s top ranking, strength in social enterprise and social issues and its location in a big European capital instantly attracted Michelle. She could continue working on her Spanish while receiving a world class education.

“Aside from cooking and tasting new foods, I am really passionate about renewable energy. It is growing a lot everyday and many of the main players are based in countries I am interested in and they interact in the most exciting ways. Working to protect our eco-system and the environment would be a unique way to implement my business skills.”

Germany

Luisa Maier, MBA at ESMT in Berlin

Being intensively involved in start-ups meant that Luisa got to experience all sides of business from operations to corporate relations to human resources to finance. However, she sensed that there was more to entrepreneurship so she she left the sun of South Africa to spend a year on the ESMT Berlin MBA.

“I want to gain more knowledge in business management and leadership and to build an amazing network of people from all over the world” she says.

“Our minds are full of business opportunities to unfold. I’m hoping that at least one or two of the ones I have buzzing in my head right now can be developed with my MBA colleagues and perhaps even brought to life after graduation”, says Luisa.

Switzerland

Nitin Misra, MBA at University of Saint Gallen HSG in Switzerland

With an impressive GMAT score of 720, the 33-year-old Indian national who has also done all the Six Flags roller coasters in the US, made soba noodles from scratch in a Japanese village, climbed Mount Fuji and lived in Newport Beach California picked St. Gallen to nurture his passion for business technology and design there.

Nitin wanted a school which had a one year programme in one of Europe’s thriving economies. Switzerland and Germany appealed to him therefore St. Gallen’s location was just perfect. He has also been able to attend courses to learn about design strategies and identifying consumer needs; and the product prototype testing and modification offered at St. Gallen’s Design school which has ties to the Stanford University Design School.

About the author: Sian Fleming Jones is a director at BusinessBecause.com – professional network for business students – helping you make connections before, during and after your MBA. You will find many more stories like the ones mentioned in this article by searching the website as well as useful information on MBA rankings, MBA jobs, and fresh daily editorial such as the Why MBA  series.

Foundational Skills

In terms of foundations skills, what you need to know for Integrated Reasoning is not really different from what you need to know for the Q & V sections.  You need to know basic math, especially percents and ratios, and you need to be able to interpret word problems.  You need to know how to read graphs.  You need to read critically and interpret, much as you do on CR and RC questions.  These are the basic skills absolutely required to negotiate the IR section, but they are not really what the IR is designed to test.

Higher Order Reasoning

The IR section is designed to assess higher order reasoning.  These skills include:

1) Integrating information, including organizing and synthesizing different kinds of information.

2) Evaluating sources of information, or evaluating tradeoffs and possible outcomes of a course of action.

3) Drawing inferences, making predictions, identifying what further conclusions are supported by the given data.

4) Interrelating information, seeing how parts fit together in context

5) Formulating strategy, deciding among possible plans of action

These are all skills that managers need for success in the business world.  These are skills that business school professors reinforce and assess.  This is precisely why hundreds of business school faculty from around the world provided GMAC with the feedback that lead to the creation of the IR section.

Relish the Challenge!

Yes, there are challenges associated with the new IR section.  Ultimately, the challenges of the IR section are closely related to the challenges you will experience in business school and as a manager in the business world.  These challenges, these opportunities to apply your creativity and insight to complex problems, are part of what make the business world engaging, even exhilarating, for folks.  This is the exciting world you are entering, and it starts for real when you sit for the “next generation” GMAT and face the IR section.  Do everything you can to prepare, so that when you face the IR section, you can bring your best to the challenge.

How to prepare?  Sign up for Magoosh, and we will help you be the best you can be on test day.

A host of complex and interesting adjectives end in “-al”, including adjectival, mercurial, floral, diurnal, banal, nominal, cardinal, terrestrial, vestigial, perennial, and epiphenomenal.  Incidentally, those would all be good words with which to have at least passing familiarity on the GMAT.

Fact: When an adjective ends in “-ic”, the “-al” ending can be added, and usually this doesn’t result in a large change in meaning.  The “-ic” and “ical” forms of the adjective may differ in connotation, in subtle implications, or they may mean exactly the same thing.

For example

• “electric” and “electrical” both mean “relating to electricity”.  Technically, if the object has electricity running through it, if it operates on electricity, one uses “electric” (i.e. an electric blender, an electric car, etc.); by contrast, if the word pertains to electricity but doesn’t run on electricity, one uses “electrical” (electrical tape, an electrical engineer, etc.)  That subtle difference is highly unlikely to be tested on the GMAT.
• “comic” and “comical” both mean “causing laughter.”  Technically, the word “comic” is used for works or situations that were intentionally created to be funny, whereas the word “comical” often denotes situations which are unintentionally humorous.  That subtle difference is highly unlikely to be tested on the GMAT.
• both “ironic” and “ironical” relate to “irony”, itself a word notoriously hard to define precisely.  The difference between “ironic” and “ironical” carries us into some of the most philosophically refined parts of English grammar.  You need not worry about this one on GMAT Sentence Correction.

Fact: Ironically, one “-ic” adjective changes its meaning drastically when “-al” is added — “economic” vs. “economical” — and this one, not surprisingly, runs rife through the entire Verbal section of the GMAT.

economic — pertaining to the discipline of economics or to the nature of an economy

economical —- saving money; thrifty; giving good value for price

The difference here is stark: in contexts in which one of these is right, the other would be 100% wrong.  Of course, the irony is: this on the GMAT, the test which prepares you for business school, where you will study nothing but economic concerns.  Just by the very nature of the test and its intent, “economic” is one of the most likely adjectives in the English language to appear on the test!  Needless to say, the economic/economical distinction is a favorite of GMAC’s, and economic/economical splits are perhaps my favorite of all possible SC answer choice splits.

Here’s an example from the OG (OG12e, #37; OG 13e, #39):

39) Although shistosomiasis is not often fatal, it is often so debilitating that is has become an economic drain on many developing countries.

1. it is often so debilitating that is has become an economic
2. it is of such debilitation, it has become an economical
3. so debilitating is it as to become an economic
4. such is its debilitation, it becomes an economical
5. there is so much debilitation that it has become an economical

Let’s start with the split in the final word of the five answer choices: economic vs. economical.  We are talking about the drain that the costs associated with shistosomiasis impose on the economy of a developing country.  In other words, we need an adjective that pertains to a country’s economy: that would be “economic.”  By contrast, an “economical drain” would be a money-saving way to lose money??? That makes no sense!!  Clearly, “economic” is correct and “economical” is completely incorrect: right there you can eliminate (B), (D), and (E), thereby enormously simplifying the task of answering this question.

While we’re discussing this question, also mention a couple other relevant points.  First of all, “so X that Y” is the correct idiom, whereas “so X as to Y” is incorrect.  That’s why (A) is correct and (C) is incorrect, and this leaves (A) as the only possible correct answer.  Also, notice that the answers flip/flop between “debilitating” (the participle form of a verb) and “debilitation” (a noun).  Which do you think is more active, a noun or a participle?  Verbs are the very essence of action, so any verb form will be more active, more vital, than a static noun.  Furthermore, strong, direct, active writing is strongly favored on the GMAT.  Therefore, it’s a good bet that if a particular word flip-flops between noun form and verb form among the five answer choices on a GMAT SC question, the correct answer often will involve the verb form, as it does in this question.

Keep an eye out for the economic/economical differences on the GMAT, throughout the Verbal section, and in some questions like the one above, it will be a magic key of simplification.

Guidebook writer: I have visited hotels throughout the country and have noticed that in those built before 1930 the quality of the original carpentry work is generally superior to that in hotels build afterwards.  Clearly carpenters working on hotels before 1930 typically worked with more skill, car, and effort than carpenters who have worked on hotels build subsequently.

Which of the following, if true, most seriously weakens the guidebooks writer’s argument?

1. The quality of original carpentry in hotels is general far superior to the quality of carpentry in other structures, such as houses and stores.
2. Hotels build since 1930 can generally accommodate more guests than those build before 1930.
3. The materials available to carpenters working before 1930 were not significantly different in quality from the materials available to carpenters working after 1930.
4. The better the quality of original carpentry in a building, the less likely that building is to fall into disuse and be demolished.
5. The average length of apprenticeship for carpenters has declines significantly since 1930.

It may be helpful to think through this question on your own before you read the full analysis below.

Do you need to study formal logic to master the GMAT Critical Reasoning?

The short answer is: no.   If you have studied formal logic, then chances are good that the “muscles” you developed in those studies also will help you with CR.  But, if you have never studied formal logic, don’t go out of your way to read up on Quine.  It’s somewhat beside the point.

Formal Logic vs. Contextual Logic

On the GMAT CR, you will not see words like “necessary”, “sufficient”, “if and only if” —- i.e. the words of formal logic.  You will see an occasional if-then statement, and other statements that could be recast as if-then statements, but results of formal logic are very seldom at the heart of what the CR is testing.

CR is all about what I would call contextual logic: here’s a real world scenario, and given the unique particularity of this situation, what would make the most sense in context?  In many CR question, the correct answer provides new information that you have to integrate with the understanding developed from the prompt.  It’s rare that you can “logically deduce” the correct answer purely from the prompt, without any reference to the answer choices.  It’s true that, for certain CR question types, it’s helpful to anticipate the answers before you start analyzing the answer choices, but the point is: pure logic is not enough.  You must be sensitive to the peculiarity of the context.

An Example of CR Logic

Let’s go back the CR questions at the head of this article.

Guidebook writer: I have visited hotels throughout the country and have noticed that in those built before 1930 the quality of the original carpentry work is generally superior to that in hotels build afterwards.  [This is a factual observation.]  Clearly carpenters working on hotels before 1930 typically worked with more skill, car, and effort than carpenters who have worked on hotels build subsequently.  [This is a conclusion that would explain the factual observation.]

We are asked to weaken the argument.  This means, we have to find another explanation for the factual observation (pre-1930 have good carpentry) that would support it even when the conclusion (pre-1930 carpenters were better than carpenters since).  In other words, even if pre-1930 carpenters are no better than later carpenters, why would the critic still observes much higher proportions of good carpentry in pre-1930 hotels?

Notice, some logical reflection has clarified our task for us, but there’s really no glaringly obvious alternate explanation for the higher proportions of good carpentry in pre-1930 hotels.  We will have to look for relevant perspectives among the answer choices.

A. The quality of original carpentry in hotels is general far superior to the quality of carpentry in other structures, such as houses and stores.

True, but not helpful.  Pre-1930 hotels had better carpentry than pre-1930 houses and stores. Post-1930 hotels have better carpentry than post-1930 houses and stores. This fact does not explain why any difference would not be apparent between pre-1930 hotels and post-1930 hotels.

B. Hotels build since 1930 can generally accommodate more guests than those build before 1930.

How many guests a hotel can accommodate has virtually no bearing on the quality of the carpentry.  If the observations about differences in quality of carpentry were made from some kind of survey of hundreds of hotel guests, perhaps we could deduce that more had stayed in pre-1930 hotels simply because those hotels can accommodate more guests.  But, the observation was in fact made by a single guidebook writer, a single person, who presumably stayed in a very large number of hotels.  That persons conclusions presumably would have absolutely nothing to do with how many other people are staying in the hotel.  This fact may well be true, but it’s irrelevant to this argument.

C. The materials available to carpenters working before 1930 were not significantly different in quality from the materials available to carpenters working after 1930.

Same materials in both time periods would not provide an alternative explanation for the difference in quality between pre-1930 and post-1930 hotels.  In fact, arguably, this fact would strengthen the argument, not weaken it.

D. The better the quality of original carpentry in a building, the less likely that building is to fall into disuse and be demolished.

This is fascinating.  Old buildings with fine carpentry are more likely to be around still.  Old buildings with mediocre carpentry are more likely to be no longer with us.  Remember, the guidebook writer was implicitly speaking of proportions.  The factual observation was, essentially: if we look at the proportion of pre-1930 hotel that have fine carpentry, and the proportion of post-1930 hotel that have fine carpentry, then the first proportion is greater than the second proportion.  The guidebook writer argued that differences in the quality of the carpenters caused this difference in proportions.

This new fact provides an alternative explanation.  Suppose carpenters now are just as good, just as skillful and careful, as carpenters from before 1930.  For simplicity, suppose, on average, 3% of hotels built have fine carpentry, and the other 97% have mediocre/substandard carpentry, and assume that was just as true before 1930 as it is now.  For hotels build before 1930, essentially all of those hotels with poor carpentry would have been knocked down, and the only ones still standing would be the 3% that had fine carpentry.  Thus, when the guidebook writer goes to pre-1930 hotels still standing, still in service, the carpentry in almost all of them is of high quality.  By contrast, hotels build in the past decade are all still standing, regardless of the quality of the carpentry.  When the guidebook writer goes to these, only 3% have fine carpentry, and the rest do not.  Thus, the guidebook writer could experience vast differences in the proportion of hotels with fine carpentry, and it would have nothing to do with the inherent quality of the respective carpenters.  This is the correct answer.

E. The average length of apprenticeship for carpenters has declines significantly since 1930.

If anything, this would strengthen the argument.  It would explain why pre-1930 carpenters would be more skillful.  This does not weaken the argument.

Notice that we were asked to weaken the argument, and a couple of the answers did the opposite: provided information to strengthen the argument.  That’s a typical GMAT CR pattern.  Similarly, when you are asked to strengthen an argument, expect to see a couple answer choices that weaken the argument.

Notice, also, in all five answer choices, our reasoning was deeply bound to the context itself.  We had to think through the details of the context to separate what was relevant from what was not relevant.  That is quite different from the exercises of formal logic, which tends toward abstraction.  GMAT CR logic is all about getting our hand dirty in the rough and tumble of real-world issues.  That what the GMAT asks you to do because, once you’re a manager with your MBA and you’re out in the business world making decisions, that’s precisely what you are going to be doing all day every day in your job.

If you want to improve your GMAT CR logic, don’t read textbooks on formal logic.  Read The Wall Street Journal and The Economist magazine: they both elucidate clearly the logic needed in the business world.

It’s logical, but …

Consider the following sentences.

1) Unlike the full gram of potassium found in a baked potato, a banana has only about 600 milligrams.

2) So upset with the low wages set in the new contract, management had to hear a long litany of complaints from the union as well as from individual factory workers.

3) Composing his first symphony a full twenty years after he became well-known as a composer, music critics were elated when Brahms finally published the piece.

In all three of those sentences, the logic is probably clear.  We know the comparison is between a baked potato and a banana.  We know the union & factory workers, not management, are the upset ones.  We know that that Brahms, not the music critics, composed the symphony.  We know all that, and in spoken-English these sentences would be clear enough.  BUT, that’s not good enough on the GMAT.  On the GMAT, it’s not enough if a sentence conveys the gist of what an author is trying to say.  On GMAT Sentence Correction, the grammar and logic must be in complete agreement.

Grammar vs. Logic

All three of those sentences would be incorrect on GMAT SC.  In the grammatical construction — “Unlike X, Y does….”, the object of the preposition “unlike” is always the first term of the comparison.  Here, in sentence #1, the object of “unlike” is “the full gram” — what follows are modifiers of “the full gram.”  The grammar is set up so that the comparison is between “the full gram” and “a banana.”  Logic tells us the comparison should be between “a baked potato” and “a banana.”  Grammar and logic suggest different things, so this is a faulty sentence.

The first part of the sentence is a modifying clause, built around the adjective “upset.”  By the Modifier Touch Rule, the very next noun the clause touches is what it modifies, and in this case, that’s “management.”  Thus, according to the grammar, management is upset.  But the logic of the overall sentence suggests: no, the union and the factory-workers are the ones who are upset — after all, these latter are the ones complaining!  Grammar and logic suggest different things, so this is a faulty sentence.

The first part of the sentence is a participial phrase, built around the participle “composing.”  This participial phrase touches “music critics”, so according to the Modifier Touch Rule, the grammar suggests that the music critics composed the symphony.  But, we know that Johannes Brahms (1833-1897) was a composer — in fact, one of the “three B’s”, the three premier composers.  Logically, we know that Brahms, not the music critics, wrote the symphony in question, Symphony #1 in C minor, Op. 68.  Grammar and logic suggest different things, so this is a faulty sentence.  (Are you sensing a pattern?)

Harmony

Our standards on GMAT Sentence Correction must be higher than they are in everyday spoken English.  In spoken English, in many situations, it’s often enough to make the logic, the meaning, clear.  That alone is not good enough on the GMAT.  In a well-crafted GMAT sentence, the grammar and logic must be in harmony, must be united in supporting the same interpretation.

As examples of this, here are possible corrected versions of those three sentences.

1)  Unlike a baked potato, with a full gram of potassium, a banana has only about 600 milligrams.

2) So upset with the low wages set in the new contract, the union andindividual factory workers laced into management with long litany of complaints.

3a) Composing his first symphony a full twenty years after he became well-known as a composer, Brahms elated music critics when he finally published the piece.

3b) Brahms composed his first symphony a full twenty years after he became well-known as a composer, and music critics were elated when he finally published the piece.

When your grammar and logic are aligned, your writing is that much more powerful and persuasive.  That is exactly what will further your career when you write in the business world.  Therefore, this is exactly what the GMAT rewards on Sentence Correction.

Here’s a related SC question, to practice these ideas further.

http://gmat.magoosh.com/questions/1112

Fact: Right now, the GMAT has a Verbal Section (75 min), a Quantitative Section (75 min), and two Analytical Writing Assessment (AWA) essays (Analysis of Argument and Analysis of Issue, 30 minutes each).

Fact: Right now, your GMAT score report tells you: (a) V score, (b) Q score, (c) a Total score (combination of your V & Q scores), and (d) AWA score.

Fact: The “next generation” GMAT will debut on Tuesday, June 5, 2012.  This test will have a V Section, a Q Section, and a single AWA essay, and the new Integrated Reasoning (IR) section.  The sequence of the new test will be

1) AWA essay = Analysis of Argument, 30 minutes

2) IR section = 12 questions, 30 minutes

3) optional break, up to 5 minutes

4) Q section = 37 questions, 75 minutes

5) optional break, up to 5 minutes

6) V section = 41 questions, 75 minutes

Fact: the IR section consists of four question types

a) Graphics Interpretation (GI)

b) Two-Part Analysis (2PA)

c) Table Analysis (TA)

d) Multi-Source Reasoning (MSR)

Fact: all four question types will appear on everyone’s IR sections.

Fact: the breakdown by question type will differ from one person’s IR section to another person’s only because of the experimental questions.

In other words, for the questions on which you are actually graded, which actually count toward your score, everyone will have the same breakdown by question type; extra experimental questions added to that baseline will give different people’s IR sections different breakdowns.

GMAC has revealed neither what that fundamental breakdown is, nor how many of the 12 questions will be experimental.  Let’s just take a pretend scenario, just to understand.  Let’s say: the graded IR questions consist of 2 GIs, 2 2PAs, 2 TAs, and 2 MSRs, for a total of eight (these are my made-up numbers).  For everyone taking the test, let’s say those are the eight questions that are graded.  The other four questions would be experimental questions, and will be different for different users.  Thus, Abe might get an IR section with 3 GIs, 3 2PAs, 3 TAs, and 3 MSRs.  Betsy might get an IR section with 2 GIs, 3 2PAs, 3 TAs, and 4 MSRs. Cathy might get an IR section with 2 GIs, 6 2PAs, 2 TAs, and 2 MSRs.  In each case, only the baseline eight questions count toward the score, and the others are experiments.  (The numbers in this example are purely hypothetical: we have no idea what GMAC has up their sleeve.)

Here’s the kicker, though.  As our hypothetical friend Cathy is working through her IR section, she may start to think: Gee, I’m seeing a lot of 2PA questions!  Some of them must be experimental!  Quite true.  The catch is, among those six 2 PA questions, the two that count could be the first two, or the last two, or any combination.  There are actually 15 different ways that the two that count could be scrambled among the four experimental questions.  As the test taker, even if you do have strong suspicions about which question types the experimental questions were, you will have no way of knowing, as you are working on a particular question, whether it counts or is experimental.  Therefore, you have to treat every single question as if it counts, same as on the Q & V sections.

Fact: the IR section is not computer adaptive.  You are randomly assigned 12 questions as a group, and move through that sequence regardless of whether you are getting questions right or wrong.

Fact: The “next generation” GMAT score report will consist of  (a) V score, (b) Q score, (c) a Total score (combination of your V & Q scores), (d) AWA score, and (e) IR score.

Fact: the IR score will be an integer from 1 to 8.  THERE IS NO PARTIAL CREDIT ON THE INTEGRATED REASONING SECTION.  There is no partial credit on the IR section.  For example, in a TA question in which there are three dichotomous prompts (e.g. true/false), you must get all three right to get credit for that one question.  If you get at least one of the three wrong, the whole question is wrong.

Fact: The number of IR questions you get right will constitute a raw score.  The GMAC, using an arcane alchemy known only to them, will convert that raw score to a scaled score (1 – 8), which will be accompanied by percentiles.

Notice: Because of the statistical magic GMAC uses in converting raw scores to scaled scores (on IR, Q, & V sections), what may seem to your advantage or disadvantage may not work out that way.  For example, the fact that there’s no partial credit is challenging: it makes it harder to earn points on individual questions.  BUT, harder for everyone means lower raw scores are needed to get a high percentile grade.  Similarly, if all the questions are very easy, that means most people will get them right, which means it will be “crowded” at the top, much harder to place in a high percentile.  What matters is not how inherently easy or hard the test is: what matters is how well you perform, compared to other test takers.

Given your inherent talents, what will maximize your GMAT skills with respect to others taking the GMAT?  Sign up for Magoosh, and you will learn all the content and strategy you will need.

The following sentences appear in the directions to the GMAT Problem Solving questions.

A figure accompanying a problem solving questions is intended to provide information useful in solving the problem.  Figures are drawn as accurately as possible.  Exceptions will be clearly noted.

Many GMAT-takers underestimate the valuable information given there.  Diagrams on GMAT Problem Solving are basically drawn to scale.  The only time that doesn’t hold is if you see the note printed “Diagram not necessarily to scale” — then, all bets are off about how the figure actually looks.  But if that disclaimer is not printed, what you have on GMAT Problem-Solving is a diagram drawn to scale, guaranteed.

What You Can Assume

Consider the following question:

1) The area of rectangle ABCD is closest to which of the following?

(A) 100

(B) 130

(C) 170

(D) 200

(E) 230

Suppose we don’t know the math to answer this question.  We are told it’s a rectangle, so we know the angles must be right angles, and we know the area must be length (AD) times height (AB).  We know the height is 10.  We know AD is drawn to scale.  It definitely is longer than AB, so the area is definitely larger than 10 x 10 (answer (A) is out).  AD doesn’t look as long as twice AB, so the area is definitely less than 10 x 20 (answers (D) & (E) are out).  Notice, with pure spatial estimation, we eliminated three of the five answer choices, so it will be to our advantage to guess randomly from the remaining two if we can’t decide between them.  Estimating from size can be a huge help if you don’t remember the way to solve the problem.

BTW, the real math solution to that question:  from the properties of the 30-60-90 triangle (ACD), we know that AD = 10*sqrt(3), and since sqrt(3) is approximately 1.7, AD is approximately 17, and the area is approximately 170. Answer = C.

Here’s another.  This is from the GMAT OG.  In the GMAT OG12e, it’s Problem Solving #210, and in the OG13e, it’s Problem Solving #211.

2) In the coordinate system above, which of the following is the equation of line l?

(A) 2x – 3y = 6

(B) 2x + 3y = 6

(C) 3x + 2y = 6

(D) 2x – 3y = –6

(E) 3x – 2y =–6

A student asked about this question: how do we know that the x-intercept of line l is 3 and the y-intercept is 2?  Well, technically, we don’t know that they are exactly 3 and 2, but we know from the diagram that if they are not exactly 3 and 2, they are very very close.  Thus, x-intercept = 3 and y-intercept= 2 make an excellent starting point: even if they are not spot-on correct, they are very good approximations.  As it happens, the exact values themselves lead to the correct answer of B.

What You Can’t Assume

You can’t assume lines are parallel, because many special properties are true only if two lines are exactly parallel, but the naked eye cannot distinguish exactly parallel from almost parallel.  For example:

These lines look parallel, right?  They’re not: they are 1/10 of one degree off from exactly parallel, and that means: none of the special geometry facts for parallel lines would apply to these lines.

The same applies to right angles.  An angle of 89.9º or 90.1º will look like a right angle to the unaided eye, but if it’s not an exact right angle, none of the special right angle facts (like the Pythagorean Theorem) will apply.  For example:

These are two squares, right?  Think again.  Here is each one with individual measurements:

ABCD is actually a rhombus: four equal sides, and opposite pairs of angles equal, but not equiangular, the way a square should be.

EFGH is actually an isosceles trapezoid: equal pairs of base angles, and the legs (EF & GH) are congruent.  Both look like squares, but neither one is.

None of the parallel properties in geometry are true for “almost parallel,” and none of the right angle properties are true for “almost a right angle.”

The Moral

Diagrams on GMAT Problem Solving are drawn to scale.  That serves you very well when you are approximating.  That doesn’t help you, and may mislead you, if you need something to be exactly true.

Here’s a practice PS question with a diagram drawn to scale:

http://gmat.magoosh.com/questions/106