December 18, 2012
The holidays are upon us, and with them come a flurry of seasonal activities: shopping trips, parties, and visits with family and friends. If you’re planning on taking your GMAT in January, you’re probably struggling with the challenge of fitting your studies into your holiday schedule. Here are a few tips to help you make the most of this busy time.
First, acknowledge your limitations. Because of your holiday obligations, you’ll probably need to scale back your GMAT study time. The holidays provide you with a great opportunity to recharge mentally and emotionally, so there’s nothing wrong with cutting back a little on your studies to give yourself some more personal time. You’ll be able to create a study schedule–and stick to it–if you’re realistic with yourself about how much time you’ll actually have for studying over the holidays.
Second, since you’ll have less time to study, plan out carefully what you’re going to study and when. A specific agenda for each study session will help guarantee that you use your productively. If you’re used to longer study sessions (two or three hours), but you’ll be studying for shorter periods during the holidays, limit your agenda to one key topic at a time. For instance, you might spend an hour reviewing just proportions, rather than two hours reviewing proportions, averages, and ratios. This is also a good time to give yourself short quizzes (5 to 10 questions at time); in an hour, you can complete a short quiz in 15 to 30 minutes, giving you an equal amount of time to use for review of the quiz. As always, though, be sure to balance your studying between Quant and Verbal. A good plan is alternating between the two every day, or depending on your individual strengths and weaknesses, spending two days on one, followed by one day on the other.
Finally, recognize that there are benefits to a mini-vacation from your studies. Taking time away from intense studying gives you time to digest the material. There’s a lot to learn for the GMAT, and all that material takes time to “settle in” to your brain. Slowing down for a little while allows you to master concepts and helps prevent burn out. So take advantage of the pleasures of the holidays: enjoy your time spent not studying, maximize the time you do spend studying, and rest assured that your brain will benefit from the holiday as well.
October 1, 2012
A few months ago I had a student in one of my GMAT classes tell me her study plan. She was very diligent and committed to the study process, and the plan was a very well thought out and detailed. Furthermore, she was executing the plan brilliantly. The problem was that her score was going nowhere. She wasn’t gaining any ground from her masterful execution. What was the problem?
After digging a bit deeper, one thing stood out. She was using all the tools: practice tests, online quizzes, workshops, workbooks etc. None of this seemed odd. In fact, it was all commendable. However, there was a fatal flaw in the way she was using these resources. She wanted to makes sure that she had the endurance to answer these questions on test day. Therefore, when she sat down to do quantitative problems, she would create a set of 37, do them all, and then review the answers. She would do 41 questions for the GMAT verbal section. This seems like a great idea, right? It’s very realistic. Wrong!!!
This is the same challenge that Toyota solved with lean processes and the Lean Startup movement is busy solving in the entrepreneurial world. Working in large batches seems reasonable and efficient. However, when our goal is learning and validation, it is counterproductive in a big way. Now, we could spend a lot of time diving deep into either lean manufacturing or lean startup methods, and that would be a lot of fun. However, let’s stay on point and look at how it works with GMAT studying.
To complete 37 questions will take you about 75 minutes. During this time you are busy answering the questions. This practice is good, but you aren’t adding new knowledge to the mix. You are just moving along the experience curve and getting faster at what you know. But what if what you know is wrong? In that case, you will continue to make the same mistakes all the way through, without the benefit of learning from early mistakes.
Now imagine that you take them in batches of 5 questions and then review the answers. In this case, if you are lacking some crucial piece of knowledge, you will learn that in the first batch. Even if you got a question right, you may learn a better way to approach it. You will then be able to apply that knowledge in subsequent sets and move on to higher level challenges. By working in small batches you will do this over and over again. In this way you can compound your rate of learning and move to higher and higher scores.
As a final note on this, I thought I’d share a recent success story. I had a student who was scoring around 650 on his practice tests right up to the week before his test. His goal was mid 700’s. He was using a large batch approach as well. After making the switch to small batch study, he spent a week compounding his learning. On test day he scored a 750! Try studying in small batches….
September 6, 2012
In a blog last last week, I talked about the importance of identifying the common question types in the reading comprehension portions of the GMAT and delved into the specifics for detail and global questions. Today, let’s continue that deeper look at the specifics for the common reading comprehension questions with a look at inference and function (logic) questions. Specifically let’s look at how to spot them, how to predict using the pattern behind the question, and how to spot the most common wrong answer types. Both of these questions generally constitute the harder or more commonly missed set of questions in the reading comprehension.
One of the most commonly missed reading comprehension questions is the inference question because of how it is treated on tests versus our common everyday use of inference. First of all, to spot them you are looking either for something that references “is true” or uses “infers,” “implies,” or “suggests” in the question stem. The most common phrasing is “most likely agree” in an inference stem. Once you see any of these triggers, immediately switch your mindset to look for what MUST be true. Because the language is soft in the question stem, test-takers usually just consider and look for what COULD be true. That will lead you straight to trap answer choices. You MUST look for what MUST be true. I even started mentally adding “must it be true that…” before reading each answer choice. Trust me; this will revolutionize your approach to inference questions. In addition to looking for what MUST be true, lean toward choices that have what I would call softer or squishy wording like “some,” “could,” “likely,” etc. It’s much easier to write a MUST be true answer about some things than it is to write a MUST be true about all things.
In addition to identifying the right answer, knowing the choices that you can eliminate can be just as helpful. The most common wrong answer types on inference questions are the out of scope and extreme choices. As stated above, it’s harder to write something that MUST be true about everything. Therefore, lean away from the extreme wording. Also, many out of scope choices COULD be true, so they are appealing. Asking whether it MUST be true will help you avoid these traps.
The last of the big four reading comprehension question types is the function (logic) question. These questions ask about WHY an author included some detail in the passage. You can spot these because they commonly include a line reference and include phrasing such as “functions to,” “in order to,” or “serves to.” In order to answer these questions efficiently and effectively, look to the opinion or main idea right around that detail; context is key in these questions. Typically that means that you are looking at the author opinion that is directly above or in the topic sentence of that particular paragraph. Occasionally, the point supported can come after the detail. Expanding out beyond the lines mentioned in the question is crucial to taking care of these questions adeptly. With function questions, the traps or most common wrong answers are those that pertain to the detail but don’t answer the question why – they distort what the question is asking. To avoid these make sure you always align yourself to look at the context.
Outside of these four primary question types (detail, global, inference, and function), there are a few outliers such as application, vocab-in-context, strengthener, and weakener questions. If a question doesn’t clearly fit one of the big four, don’t try to force the pattern. The patterns take time and repeated practice to get used to, but if you want to take your reading comprehension score to the next level on test day, aligning your approach with the specifics of each type is the way to go!
August 30, 2012
Do you want to take your reading comprehension performance on the GMAT to the next level? Once you’ve developed your passage mapping, it’s time to turn your attention to the question stems. In order to truly master the questions in an effective and efficient way, knowing the nuanced and blatant differences among the question types helps you approach the question in a way that avoids the common missteps and tightens your evaluation of the answer choices.
There are really four primary question types that appear with the typical reading comprehension passage with great regularity. For our purposes right now, we’ll focus on those; however, there can be other outlier question types that appear occasionally. The main question types are global, detail, inference, and function/logic. Let’s take a look at the first two – global and detail – today.
First, global questions are so incredibly common. You can spot them because they ask for things like the “main idea,” “primary purpose,” or even a title. Just like the name implies, these questions ask about the big picture of the passage. Additionally, the author’s opinion or lack thereof is essential to tackling these questions with confidence. If you are considering the main idea, look for the author’s overall opinion about the scope of the passage or, when there is no author opinion, just the scope. For primary purpose questions, it’s again all about author opinion and how charged that opinion is. In passages with very clear author bias, verbs like “advocate,” “argue,” or “refute” will start any answer choice that is worth consideration. In passages with very little or no author opinion, neutral verbs like “describe” or “explain” will be what you want to look for. No matter what form the global question takes, the main trap choices are those that are too narrow or only deal with a small portion of the passage. In order to avoid this, keep your eye on big picture and author opinion as you read.
Secondly, detail questions are deceptively simple because they ask about very specific points in the passage. In order to spot these questions, look for wording such as “according to …” or “the ___ states.” As long as something in the question stem doesn’t tip it over to inference from there, you are looking for something that was directly stated in the passage. The primary thing that test-takers do with detail questions is rely on their short-term memory to answer these because they don’t want to go back and spend more time in the passage. However, the test-makers build in amazing traps in detail questions. Be on the lookout for choices that are misused details, specifics from the passage that don’t answer the question. These feel familiar because they were in the passage, so they are commonly chosen. Also, there are many choices that are distortions in detail questions; these choices start out beautifully but take a turn at the end that steps outside of the bounds of the passage. Because many test-takers don’t truly read the answer choice all the way through, these are common trap choices. In order to avoid both, go back and quickly verify the correct detail; with a good map, this is a quick process.
We’ll look at the other two primary reading comprehension question types next week. In the meantime, practice spotting these two in your GMAT prep. Align yourself to predict in a way that is appropriate for the question type, and you will find your performance on these types quickly tightening. Finally, being armed against the most common wrong answer types for each is also essential to effective and efficient management of these questions. So until next week, happy studying and happy reading!
August 25, 2012
As you likely know, with the inclusion of the Integrated Reasoning (IR) section came the exclusion of the one of the previously required essays. Before the test change, GMAT test takers built their Analytical Writing Assessment (AWA) score on the backs of two essays: Analysis of an Argument and Analysis of an Issue. These two essays would be scored independently—by one human and one computer—then those two scores would be averaged for a total AWA score on a 0-6 point scale in ½-point increments. In order to keep total testing time at 3.5 hours, test makers decided to cut the thirty-minute Analysis of an Issue essay and insert a thirty-minute Integrated Reasoning section.
So what can we make of this decision? Now, let’s not bicker about the Integrated Reasoning section here; it is what it is and we all have to deal with it. Rather, let’s focus on the essay left standing. Since we still have to write, are we better off with the Argument essay over the Issue essay? And, if so, is there a way we can ensure a top-scoring essay on test day? Good news: yes and yes.
First, writing an Argument essay over an Issue essay is preferable because of all the work we do studying GMAT Critical Reasoning (CR) questions. Seventy percent of CR questions we will see on test day will come from what is known as the Assumption Family of question types (aka, the Argument Family). In each of these question types—Assumption, Strengthen, Weaken, and Flaw—we always approach in the exact same way. That is, we identify the Conclusion, then we identify the Evidence, and then we can tease out the author’s primary Assumption(s) by applying our highly tuned critical thinking skills. You see, a GMAT argument will always state both a conclusion and evidence for the conclusion. What we will never be given, what the author will never state explicitly, are the underlying assumptions that allow this evidence to lead to this conclusion. But, in order to answer Assumption Family questions we must identify what those unstated assumptions are.
The good news about the Argument essay can be summed up by “The Four Truths” present in every single essay prompt created:
- There will be a Conclusion.
- There will be Evidence.
- There will be Assumptions linking the Conclusion and Evidence.
- Those Assumptions will be flawed.
Beautiful, right? The better we get at Critical Reasoning, the easier deconstructing the AWA essay prompt will be. In the Issue essay, we had to come up with our own ideas, reasoning, and support for taking a particular position on an issue provided. However, in the Argument essay, all we need is tucked away within the prompt itself. Sure, we have to do some detective work to sniff it out, but it is comforting to know it’s there and that we definitely have developed the skill to find it.
OK, so what about the other question: Is there a sure-fire way to churn out a top-scoring essay no matter what the given argument is? You bet. Quite simply, you’ll open by restating the conclusion and evidence in your own words. Then, you’ll identify at least two flawed assumptions and explain why they are flawed—one assumption per paragraph. After that, you’ll talk about how the argument could be strengthened (here, you can just feed off of what you said was wrong with it), then you’ll wrap up with a conclusion. That’s it.
As I mentioned at the beginning of this post, your GMAT essay is going to be scored by one human and one computer. I suggest reading my previous post titled “GMAT essays: Computers score your work, and they are really good at it” to learn more about those computers. But just in case you’re running short on time, I’ll give you the gist…
When that human grader gets to your essay—you know, the one you toiled over for half an hour—what do you think that human had been doing right before your essay popped up on their screen? Grading essays. And what do you think that human is going to do after they finish with your essay? Grading essays. And how much time do you think they will devote to evaluating your little essay baby that you worked so hard to compose? Under two minutes, even as little as one. So, then, what is that human trying to do? Emulate a machine.
The aforementioned structure of an Analysis of an Argument might seem bland and formulaic, but you need to appreciate that you are writing for a machine and someone trying their darndest to act like one. Feed the machine and you will be rewarded.
Do you have more questions about the argument essay or the test change? Post them in the comments and we’ll tackle them one at a time.
August 10, 2012
We’ve already covered modifiers in GMAT sentence correction several times before. But, as one of the most common question types on the verbal section, and one of the types that requires the most finesse, there is still more to cover!
Today, I want to address a common misconception. Generally, modifiers must be placed as close as possible to the thing they modify. However, students sometimes mistake “as close as possible” for “adjacent.” Many test-takers find themselves confused when a long string of nouns, often peppered with prepositions, precedes a modifier. But as long as the modifier can be unambiguously linked to a specific part of that phrase, the sentence is grammatically correct. To illustrate, look at the following sentence, which is correct as written:
The members of parliament who attended the conference were pleased with the lush accommodations they received.
The modifier is the phrase “who attended the conference,” and the “who” follows “The members of parliament.” This setup should look suspicious, and it requires our attention—does the modifier apply to “parliament,” or to “the members of parliament”? Well in this case, “parliament” isn’t a “who”! The modifier correctly, clearly, and properly modifies “members of parliament.”
Let’s look at another one to be sure that we are clear:
The tides of the Pacific Ocean, which ebb and flow with regularity, have been the sailor’s ally for centuries.
The modifier here unambiguously refers to “tides,” and not “the Pacific Ocean,” because the plural verbs “ebb” and “flow” can’t refer to a singular Ocean. It’s also correct.
But the challenge of sentence correction lies not only in recognizing right sentences, but also in spotting errors. How could an answer choice on the GMAT get this grammar wrong? Well, for starters, the modifier could unambiguously refer to the wrong part of the noun:
Error: The cats of Hemingway House, which is characterized by extra toes on each foot, are almost as popular a tourist attraction as the House itself.
The “which” clause incorrectly describes the Hemingway House as having extra toes—not just because of the noun’s placement, but also because the verb tense is the wrong one! Of course, if the verb tense could apply to multiple parts of the noun, we’re in just as much trouble:
Error: The ruling of the High Court, which is a source of constant embarrassment for the government, has made the news once again.
This time, the singular verb “is” could refer grammatically to the “ruling” or to the “High Court”–and worse, both the ruling and the Court could reasonably be the “source of constant embarrassment!” Such ambiguity would not be considered correct on a GMAT verbal question.
Have more questions about modifiers? Post them below, and we’ll analyze them together.
August 6, 2012
As anyone who has spent any time on GMAT Sentence Correction can tell you, the English language is complex. SC problems will frequently test idioms and tricky verb tenses, among other things. But despite a few exceptions (do you know the difference between economic and economical?), subtle shifts in the meanings of similar words aren’t usually tested in GMAT sentences. They are, however, tested on Critical Reasoning and Analytical Writing prompts.
Assumptions on the GMAT occur when the scope of discussion shifts between the evidence and the conclusion. In an earlier article, I discussed a stimulus involving burgers. One such “scope shift” in that article was that the evidence discussed cholesterol, while the conclusion discussed health in general; another involved evidence about a price reduction and a conclusion about increased consumption of burgers. Some of these are easier to spot than others, but all of them involve looking for changes in terms and terminology.
But sometimes, there is a change of meaning, even though the actual words are the same. Consider the following example:
Buddy claims he hurt his back lifting a heavy box of yogurt onto the store’s shelves. However, he was in the “diet” section of the store, stocking shelves with light yogurt. Clearly the only boxes he lifted were light; his claim for workers compensation must be a fabrication.
This argument is, of course, absurd! But if you’re locked into the GMAT mode of thinking (which is a good thing!) you might wonder why. This problem doesn’t seem to shift scope—both the evidence and the conclusion talk about the yogurt being light, right?
The key is that the author is “equivocating,” a technical term for using the same word with different meanings. “Light” here means “Diet” in the evidence but “Not Heavy” in the conclusion—that’s a pretty big gap, leading to deeply flawed reasoning. This pattern isn’t terribly common on GMAT problems, but it shows up from time to time, usually on Flaw questions. Keep your eyes peeled for words with multiple, ambiguous, or unclear meanings on the GMAT, and on today’s question of the day, an AWA prompt.
The following appeared in an internal memo for the Weekly Globe newspaper.
The proposal to reduce the celebrity section of our print edition from 6 pages weekly to 2 pages is misguided. The celebrity pages on our website average more hits per article than does any other section of our website; clearly the public is most interested in celebrity news. The proposed change would not only hurt our profits, but also betray our dedication to serving the public’s interests.
Discuss how well reasoned…
Post your analysis below, and we’ll let you know if there is anything you missed.
July 18, 2012
Listen to a politician speaking, and you’ll hear a lot of platitudes and vague statements. Occasionally, a senator or congressman will make a statement about a specific number or an exact proposal; rarely, those statements will even be correct. But mostly, you’ll hear things like, “the hidden costs will total billions,” or “this program will have far-reaching negative impacts,” or “some have suggested that this proposed law will do nothing but enrich corporations.”
When you think about it, these claims make perfect sense. With a claim as vague as the ones above, it’s hard to be proven wrong or caught in a lie. For instance, “hidden costs” could refer to net costs, but it also could refer to gross costs even if the proposal actually netted a profit. “Billions” could refer to two billion, or it could refer to two hundred billion!
In other words, the vaguer the claim, the more likely it is to be true. And on GMAT Critical Reasoning Inference questions, which ask you to identify what must be true on the basis of a short statement, the vaguest answer is most likely to be correct.
It may seem contradictory that strong words like “must” are rarely the answer to a question that asks what “must be true.” But when you think about it, it makes sense. It’s very, very easy to conclude something is possible. It’s much harder to prove something is certain. For instance, it can be easy to prove that a type of thing might have a certain quality—for instance, you can prove that some swans are white by pointing to a single white swan. But proving that all those things have that quality requires you to rule out every possible exception. Even if you show me 999 white swans, the 1,000th swan might turn out to be black!
You should always spend a few moments trying to predict the answer to an Inference question, even though it’s not always possible. And if the answer is too hard to predict, your next step should be to carefully check the answers for one that must be true. But sometimes, the computer adaptive test will give you a very high-difficulty problem, or you’ll be stuck between two answer choices, or you just won’t have time and need to guess strategically on a problem or two to beat the clock. And in those cases, picking the vaguest answer is one of the most reliable guessing strategies on the GMAT.
Consider the following GMAT practice problem. Without reading the text, can you figure out which answer is most likely correct? Then, go through the whole problem properly, and see why it’s a good fit. Good luck!
Randall: Many of the productions of my plays by
amateur theater groups are poorly done, and such
interpretations do not provide a true measure of my
skills as a dramatist.
Which one of the following can be properly inferred
from Randall’s statement?
(A) Some amateur theater groups’ productions of
Randall’s plays provide a true measure of his
skills as a dramatist.
(B) All amateur theater group productions of
Randall’s plays that are not poorly done provide
a true measure of his skills as a dramatist.
(C) All of the productions of Randall’s plays by
amateur theater groups that do not provide a
true measure of his skills as a dramatist are
(D) If a production of a dramatist’s play is well done,
then it provides a true measure of his or her
skills as a dramatist.
(E) At least some amateur theatrical groups’
productions of Randall’s plays fail to provide a
true measure of his skills as a dramatist.
Step 1: Identify the Question Type
The keywords “properly inferred” in
the question stem are a sure sign of an
Step 2: Untangle the Stimulus
Randall’s comments can be reduced
to an if/then statement: If productions
of his plays are poorly done, then they
don’t provide a true measure of his
skills as a dramatist. And many amateur
theater groups perform his plays poorly.
Step 3: Predict the Answer
While we may not be able to predict
what the correct answer choice will
infer, we can be certain that it is a
statement that must be true if we accept
Randall’s statement as true.
Step 4: Evaluate the Choices
Since many amateur productions
are poorly done, and no poorly done
production provides a true measure of
Randall’s skills, it must be true that at
least some amateur groups’ productions
do not provide a true measure of his
skills, so (E) is correct. Don’t be afraid
of (E) because it seems “obvious.” This
is not a test maker trick—an “obvious”
answer is one that must be true, so it
works as a valid Inference. (A) seriously
distorts Randall’s statement. Just
because some amateur productions
don’t do him justice doesn’t mean that
there are other productions that do. If
the GMAT tells you that some marbles
are red, you can’t automatically infer
that some are not red. (B) is another
sort of distortion. Randall’s statement
about certain poorly done productions
in no way guarantees anything about
productions that aren’t poorly done.
(C) is far too extreme. Randall does
establish a correlation between poor
production quality and failure to provide
a true measure of his skills, but that
correlation has only been established
for a certain set of productions and
can’t be extended to all productions.
(D) attempts to extract a broad principle
from Randall’s statement, but his
statement is too particular to allow this
kind of extrapolation.
The answer is (E).
July 11, 2012
You might guess that I’m on a diet, perhaps, or maybe that I’m lactose intolerant. Or maybe it’s not the milk that’s the problem; I could be deathly allergic to chocolate. Or, you might infer (correctly) that I just don’t like the flavor.
What could you infer if the GMAT told you that I don’t eat chocolate ice cream?
You can infer that if I eat ice cream, I will always choose a flavor other than chocolate. And that’s about it.
The Inference category of GMAT Critical Reasoning questions asks you to make logically supported inferences. You take the text of the stimulus at its word (recognize these questions by language such as “If the statements above are true”), and find the answer choice that must be true on the basis of the prompt.
In your GMAT prep, you will find that the biggest challenge to solving Inference questions is that there are lots of things that could be true. Sometimes, you can cleverly piece together a puzzle and make a solid prediction. But unlike argument-based Assumption questions, Inference Q’s don’t always lend themselves to knowing the answer before you look at the choices. For instance, if I don’t eat chocolate ice cream, you can infer that I wouldn’t eat chocolate ice cream cake (which contains chocolate ice cream), that a friend who knows my dietary preferences wouldn’t buy me a scoop of chocolate ice cream (which I wouldn’t eat), and that I am more likely to be seen eating vanilla ice cream than eating chocolate ice cream (because I may or may not eat vanilla ice cream, but I certainly will not eat chocolate ice cream). Since any of these would be an acceptable answer, but only one can appear in the answer choices, trying to pin down the right answer without looking at the choices can be inefficient. Inference questions are the only CR question type where you should plan to go through all five answer choices looking for one that sounds good.
But be aware of out-of-scope traps. You have to go by what the text tells you, and nothing else. And you must be able to determine the correct answer with certainty. In the chocolate ice cream example, you don’t know if the “chocolate” or the “ice cream” is the reason that I don’t eat chocolate ice cream (or something else entirely!). You might guess that I prefer vanilla ice cream, but maybe I can’t digest the milk in any type of ice cream. You might suppose that I don’t like chocolate, but it’s possible that chocolate only tastes bad to me in ice cream form and I’m fine with chocolate bars and chocolate chips. These are the types of reasonable suppositions you might make in real life, but not the type of Inference that the GMAT requires you to make.
A new electronic security system will only allow a single person at a time to pass
through a secure door. A computer decides whether or not to unlock a secure door
on the basis of visual clues, which it uses to identify people with proper clearance.
The shape of the head, the shape and color of the eyes, the shape and color of the
lips, and other characteristics of a person’s head and face are analyzed to determine
his or her identity. Only if the person trying to open a secure door has the required
clearance will the door unlock. Because this new system never fails, an unauthorized
person can never enter a secure door equipped with the system.
If the statements above are true, which of the following conclusions can be most
(A) The new system is sure to be enormously successful and revolutionize the
entire security industry.
(B) The new system can differentiate between people who are seeking to open a
secure door and people passing by a secure door.
(C) No two people have any facial features that are identical, for example,
(D) High costs will not make the new security system economically unviable.
(E) The new computer system is able to identify some slight facial differences
between people who look very similar, such as identical twins.
Step 1: Identify the Question Type
Since the stem asks us to accept the statements as true
and draw a conclusion on the basis of them, this is an
Step 2: Untangle the Stimulus
The stimulus tells us that a new electronic security system
is completely failsafe and will never allow an unauthorized
person through a door equipped with the system. And the
system allows an authorized person to enter solely on the
basis of the person’s appearance and facial features.
Step 3: Predict the Answer
Attempting to predict the correct inference could waste
time, but on the GMAT, to make an inference means to
determine what must be true, not just what could or might
be true. It’s crucial to approach the answer choices with
this in mind.
Step 4: Evaluate the Choices
(A) is out of scope. We have no evidence of how the
security industry is going to respond to the new system.
(B) doesn’t need to be true. The new system doesn’t need
to differentiate between people passing by the door and
people trying to enter, as long as it lets authorized people
in and keeps unauthorized people out.
(C) is too extreme.
We don’t know that any one feature cannot be the same.
All we know is that all of the features can’t be the same.
According to the stimulus, the security system examines
multiple facial features to determine identity.
(D), costs are outside the scope of this stimulus,
since the stimulus only discusses the likelihood that
unauthorized people will be able to get past the security
system and through a secure door.
(E) If one twin is authorized and the
other isn’t, we know the door must be able to tell them
apart, because the stimulus tells us that the security
system never fails. Thus, (E) must be true.