1. Whether the world is Euclidean or non-Euclidean is still an open question. However, if a star's position is predicted based on non-Euclidean geometry, then when a telescope is pointed to where the star should be, it will be there. Whereas, if the star's position is predicted based on Euclidean geometry, then when a telescope is pointed to where the star should be, it won't be there. This strongly indicates that the world is non-Euclidean. Which one of the following best expresses the main idea of the passage?
- The world may or may not be Euclidean.
- The world is probably non-Euclidean.
- The world is non-Euclidean.
- The world is Euclidean.
Explanation-
In option (2), the word "probably" properly limits the scope of the main idea, namely, that the world is probably non_Euclidean, but we can't yet state so definitively. Hence the answer is option (2). Option (1) understates the main idea. Although the opening line of the passage states that we don't know whether the world is non_Euclidean, the author goes on to give evidence that it is non Euclidean. Option (3) overstates the main idea. The author doesn't say that the world is non Euclidean, just that evidence strongly indicates that it is. Option (4) goes against the main idea of the passage.
2. Shyam Verma, senior sales officer, has trained many top salespeople in this company, including 14 who have become the top salespersons in their regions and 3 who have won the top salesperson award. Although there is an art to selling, Mr. Verma's success at training top salespeople shows that the skills required to become a top salesperson can be both taught and learned. The argument depends on which one of the following assumptions?
- Mr. Verma does not teach the hard-sell method. Nor does he teach the I'll-be-your-friend method. Instead, he stresses the professional-client relationship.
- More than 50% of the people trained by Mr. Verma went on to become successful salespeople.
- None of the successful salespeople who trained under Mr. Verma were accomplished salespersons before learning the Verma Method.
- There is a large and expanding industry dedicated to training salespeople.
Explanation-
If the salespeople trained by Mr. Verma were successful before studying under him, then clearly the argument would be specious. On the other hand, if none of the salespeople were successful before studying under him, then the argument would be strong. Hence option (3) is the correct option.
3. Nature constantly adjusts the atmospheric carbon level. An increase in the level causes the atmosphere to hold more heat, which causes more water to evaporate from the oceans, which causes increased rain. Rain washes some carbon from the air into the oceans, where it eventually becomes part of the seabed. A decrease in atmospheric carbon causes the atmosphere to hold less heat, which causes decreased evaporation from the oceans, which causes less rain, and thus less carbon is washed into the oceans. Yet some environmentalists worry that burning fossil fuels may raise atmospheric carbon to a dangerous level. It is true that a sustained increase would threaten human life. But the environmentalists should relax _ nature will continually adjust the carbon level. Which one of the following, if true, would most weaken the argument in the passage?
- Plant life cannot survive without atmospheric carbon.
- Carbon is part of the chemical "blanket" that keeps the Earth warm enough to sustain human life.
- Breathing by animals releases almost 30 times as much carbon as does the burning of fossil fuels.
- The natural adjustment process, which occurs over millions of years, allows wide fluctuations in the carbon level in the short term.
Explanation-
The counter _ premise in this argument is the sentence "It is true that a sustained increase [in atmospheric carbon] would threaten human life." The question asks us to weaken the argument. As mentioned before, to weaken an argument typically, you attack a premise (either expressed or suppressed) of the argument. One possibility the author did not account for is that the natural adjustment process may require many years and that in the short run dangerous levels of carbon could accumulate. This directly attacks the main premise of the argument, "Nature constantly adjusts the atmospheric carbon level." Hence the answer is option (4).
4. In tests for pironoma, a serious disease, a false positive result indicates that people have pironoma when, in fact, they do not and a false negative result indicates that people do not have pironoma when, in fact, they do. To detect pironoma most accurately, physicians should use the laboratory test that has the lowest proportion of false positive results. Which of the following, if true, gives the most support to the recommendation above?
- The accepted treatment for pironoma does not have damaging side effects.
- The laboratory test that has the lowest proportion of false positive results causes the same minor side effects as do the other laboratory test used to detect pironoma.
- In treating pironoma patients, it is essential to begin treatment as early as possible, since even a week of delay can result in loss of life.
- All laboratory tests to detect pironoma have the same proportion of false negative results.
Explanation-
The most accurate test for pironoma would be the one with the fewest false results. If all tests have the same proportion of false negatives, then the most accurate is the one that has the lowest proportion of false positives. Thus, (4) supports the recommendation and is the best answer. Choices (1) and (3) deal with the treatment for pironoma and are irrelevant to the accuracy of tests for pironoma. Option (2) deals with the side effects of tests for pironoma, and does not address their accuracy.
5. No one will be admitted to the IIM unless he or she studies hard for the CAT. No one studied hard for CAT unless he or she was not a graduate from Timbuktoo University. Which one of the following conclusions necessarily follows from the above statements?
- No graduate of Timbuktoo University was admitted to the IIM.
- Some graduates of Timbuktoo were admitted to the IIM.
- All graduates of Timbuktoo Studied hard for the IIM.
- Only graduates of Timbuktoo University did well on the CAT.
Explanation-
No one will be admitted to the IIM unless he or she studies hard for the CAT.' This statement implies that if a person is admitted to the IIM he or she must have studied hard for the CAT. The second statement `No one studied hard for CAT unless he or she was not a graduate from Timbuktoo University,' implies that if one is not a graduate from Timbuktoo University one would study hard for CAT. So graduates from Timbuktoo University will not study hard for CAT. As a result they will not get admitted to the IIM. This is best represented by option (1). Hence the correct answer is option (1).