GMAT Diagnostic Test - Verbal - Solutions

Test Questions

1. The petrochemical industry claims that chemical waste dumps pose no threat to people living near them. If this is true, then why do they locate the plants in sparsely populated regions? By not locating the chemical dumps in densely populated areas the petrochemical industry tacitly admits that these chemicals are potentially dangerous to the people living nearby.

Which of the following, if true, would most weaken the author's argument?
(A) Funding through the environmental Super Fund to clean up poorly run waste dumps is reserved for rural areas only.
(B) Until chemical dumps are proven 100% safe, it would be imprudent to locate them were they could potentially do the most harm.
(C) Locating the dumps in sparsely populated areas is less expensive and involves less government red tape.
(D) The potential for chemicals to leach into the water table has in the past been underestimated.
(E) People in cities are more likely to sue the industry if their health is harmed by the dumps.

Correct Answer: (C)
Solution: The suppressed false premise of the argument is that all things being equal there is no reason to prefer locating the sites in sparsely populated areas. To weaken the argument, we need to show it is not true that all things are equal. In other words, there are advantages other than safety in locating the sites in sparsely populated areas. Choice (C) gives two possible advantages--cost and ease. Hence (C) is the answer.

2. The news media is often accused of being willing to do anything for ratings. However, recent action by a television network indicates that the news media is sometimes guided by moral principle. This network had discovered through polling voters on the east coast that the Republican candidate for President had garnered enough votes to ensure victory before the polls closed on the west coast. However, the network withheld this information until the polls on the west coast closed so that the information would not affect the outcome of key congressional races.

Which one of the following most strengthens the argument?
(A) The network had endorsed the Republican candidate for President.
(B) The network expected its ratings to increase if it predicted the winner of the presidential race, and to decrease if did not predict the winner.
(C) A rival network did predict a winner of the presidential race before the polls on the west coast closed.
(D) The network believed that it would receive higher ratings by not predicting the winner of the presidential race.
(E) The network feared that predicting the winner of the presidential race could so anger Congress that it might enact legislation preventing all future polling outside of voting centers.

Correct Answer: (B)
Solution: The suppressed premise in this argument is that the network hurt itself by not predicting the winner of the presidential race, or at least did not help itself. To strengthen the argument, we need to show that this assumption is true. Choice (B) implies that this is the case by stating that the network expected to lose ratings if it did not predict a winner. Hence the answer is (B).

3. To avoid economic collapse, Russia must increase its GNP by 20%. However, due to the structure of its economy, if the 20% threshold is reached, then a 40% increase in GNP is achievable.

Assuming that the above statements are true, which one of the following must also be true?
(A) If ethnic strife continues in Russia, then a 20% increase in GNP will be unattainable.
(B) If a 40% increase in Russia's GNP is impossible, its economy will collapse.
(C) If Russia's GNP increases by 40%, its economy will not collapse.
(D) If the 20% threshold is reached, then a 40% increase in GNP is achievable and a 60% increase is probable.
(E) If Russia's economy collapses, then it will not have increased its GNP by 40%.

Correct Answer: (B)
Solution: Diagramming will show this seemingly difficult problem to be simply an application of the contrapositive rule of logic: in an if-then statement, negating the conclusion also negates the premise. The sentence "To avoid economic collapse, Russia must increase its GNP by 20%" can be reworded as "if Russia does not increase its GNP by 20%, its economy will collapse." This in turn can be symbolized as

not20%->Collapse

Where the arrow, ->, stands for "if ..., then ....

Next, symbolize the clause "if the 20% threshold is reached, then a 40% increase is achievable" as

20%->40%

Applying the contrapositive to this statement yields

not40%->not20%

Using the transitive property (If a = b and b = c, then a = c) to combine this with the first symbol statement yields

not40%->Collapse

In other words, if a 40% increase in GNP is unattainable, the economy will collapse. This is precisely what choice (B) states. The answer is (B).

In questions 4-6, part or all of each sentence is underlined. The answer-choices offer five ways of phrasing the underlined part. If you think the sentence as written is better than the alternatives, choose A, which merely repeats the underlined part; otherwise choose one of the alternatives.

4. The rising cost of government bureaucracy have made it all but impossible to reign in the budget deficit.
(A) The rising cost
(B) Since the rising costs
(C) Because of the rising costs
(D) The rising costs
(E) Rising cost

Correct Answer: (D)
Solution: Choice (A) is incorrect because the plural verb "have" does not agree with its singular subject "the rising cost."
Both (B) and (C) are incorrect because they turn the sentence into a fragment.
Choice (E) is incorrect because "rising cost" is still singular.
Choice (D) is the correct answer since now the plural verb "have" agrees with its plural subject "the rising costs."

5. Using the Hubble telescope, previously unknown galaxies are now being charted.
(A) Using the Hubble telescope, previously unknown galaxies are now being charted.
(B) Previously unknown galaxies are now being charted, using the Hubble telescope.
(C) Using the Hubble telescope, previously unknown galaxies are now being charted by astronomers.
(D) Using the Hubble telescope, astronomers are now charting previously unknown galaxies.
(E) With the aid of the Hubble telescope, previously unknown galaxies are now being charted.

Correct Answer: (D)
Solution: Choice (A) is incorrect because the phrase "using the Hubble telescope" does not have a noun to modify.
Choice (B) is incorrect because the phrase "using the Hubble telescope" still does not have a noun to modify.
Choice (C) offers a noun, "astronomers," but it is too far from the phrase "using the Hubble telescope."
In choice (E), the phrase "with the aid of the Hubble telescope" does not have a noun to modify.
Choice (D) offers a noun, "astronomers," and places it immediately after the modifying phrase "using the Hubble telescope." The answer is (D).

6. Common knowledge tells us that sensible exercise and eating properly will result in better health.
(A) eating properly will result
(B) proper diet resulted
(C) dieting will result
(D) proper diet results
(E) eating properly results

Correct Answer: (D)
Solution: Choice (A) is incorrect since "eating properly" (verb-adverb) is not parallel to "sensible exercise" (adjective-noun).
Choice (B) offers two parallel nouns, "exercise" and "diet." However, a general truth should be expressed in the present tense, not in the past tense.
Choice (C) is not parallel since it pairs the noun "exercise" with the gerund (a verb acting as a noun) "dieting."
Choice (E) makes the same mistake as choice (A).
Choice (D) offers two parallel nouns--"exercise" and "diet"--and two parallel verbs--"tells" and "results." The answer is (D).

Passage for Question 7:
As Xenophanes recognized as long ago as the sixth century before Christ, whether or not God made man in His own image, it is certain that man makes gods in his. The gods of Greek mythology first appear in the writings of Homer and Hesiod, and, from the character and actions of these picturesque and, for the most part, friendly beings, we get some idea of the men who made them and brought them to Greece.

But ritual is more fundamental than mythology, and the study of Greek ritual during recent years has shown that, beneath the belief or skepticism with which the Olympians were regarded, lay an older magic, with traditional rites for the promotion of fertility by the celebration of the annual cycle of life and death, and the propitiation of unfriendly ghosts, gods or demons. Some such survivals were doubtless widespread, and, prolonged into classical times, probably made the substance of Eleusinian and Orphic mysteries. Against this dark and dangerous background arose Olympic mythology on the one hand and early philosophy and science on the other.

In classical times the need of a creed higher than the Olympian was felt, and Aeschylus, Sophocles and Plato finally evolved from the pleasant but crude polytheism the idea of a single, supreme and righteous Zeus. But the decay of Olympus led to a revival of old and the invasion of new magic cults among the people, while some philosophers were looking to a vision of the uniformity of nature under divine and universal law.

7. The main idea of the passage is that
(A) Olympic mythology evolved from ancient rituals and gave rise to early philosophy
(B) early moves toward viewing nature as ordered by divine and universal law coincided with monotheistic impulses and the disintegration of classical mythology
(C) early philosophy followed from classical mythology
(D) the practice of science, i.e., empiricism, preceded scientific theory

Correct Answer: (B)
Solution: Most main idea questions are rather easy. This one is not--mainly, because the passage itself is not an easy read. Recall that to find the main idea of a passage, we check the last sentence of the first paragraph; if it's not there, we check the closing of the passage. Reviewing the last sentence of the first paragraph, we see that it hardly presents a statement, let alone the main idea. Turning to the closing line of the passage, however, we find the key to this question. The passage describes a struggle for ascendancy amongst four opposing philosophies: (magic and traditional rites) vs. (Olympic mythology) vs. (monotheism [Zeus]) vs. (early philosophy and science). The closing lines of the passage summarize this and add that Olympic mythology lost out to monotheism (Zeus), while magical cults enjoyed a revival and the germ of universal law was planted. Thus the answer is (B).

As to the other choices, (A) is false. "Olympic mythology [arose] on one hand and early philosophy and science on the other" (closing to paragraph two); thus they initially developed in parallel. (C) is also false. It makes the same type of error as (A). Finally, (D) is not mentioned in the passage.

DIAGNOSIS

If you missed questions 1 or 2:
Your score indicates that you need to study the function of premises and conclusions in an argument. Click Premises and Conclusions for a review of these concepts.

If you missed Question 3:
Your score indicates that you need to study the contrapositive rule of logic. Click Contrapositive for a review of this critical concept.

If you missed Question 4:
Your score indicates that you need to study the function of subjects and verbs in sentences. Click Subject-Verb Agreement for a review of this critical concept.

If you missed Question 5:
Your score indicates that you need to study the function of misplaced modifiers in sentences. Click Misplaced Modifiers for a review of this critical concept.

If you missed Question 6:
Your score indicates that you need to study the function of faulty parallelism in sentences. Click Faulty Parallelism for a review of this critical concept.

If you missed Question 7:
Your score indicates that you need to study the function of main idea questions. Click Main Idea Questions for a review of this critical concept.

PERFORMANCE

If you perform at this level on a complete GMAT Verbal section, your score would be as follows:

Conversion Chart:

Raw Score	Scaled Score
1	18
2	24
3	29
4	33
5	38
6	43
7	50