Wednesday, March 11, 2009

CR Question 48, 49

48). Black Americans are, on the whole, about twice as likely as White Americans to develop high blood pressure. This likelihood also holds for westernized Black Africans when compared to White Africans.
Researchers have hypothesized that this predisposition in westernized Blacks may reflect an interaction between western high-salt diets and genes that adapted to an environmental scarcity of salt.

Which of the following statements about present-day, westernized Black Africans, if true, would most tend to confirm the researchers' hypothesis?

(A) The blood pressures of those descended from peoples situated throughout their history in Senegal and Gambia, where salt was always available, are low.

(B) The unusually high salt consumption in certain areas of Africa represents a serious health problem.

(C) Because of their blood pressure levels, most White Africans have markedly decreased their salt consumption.

(D) Blood pressures are low among the Yoruba, who, throughout their history, have been situated far inland from sources of sea salt and far south of Saharan salt mines

(E) No significant differences in salt metabolism have been found between those people who have had salt available throughout their history and those who have not.

49). The spacing of the four holes on a fragment of a bone flute excavated at a Neanderthal campsite is just what is required to play the third through sixth notes of the diatonic scale—the seven-note musical scale used in much of Western music since the Renaissance. Musicologists therefore hypothesize that the diatonic musical scale was developed and used thousands of years before it was adopted by Western musicians.

Which of the following, if true, most strongly supports the hypothesis?

(A) Bone flutes were probably the only musical instrument made by Neanderthals.

(B) No musical instrument that is known to have used a diatomic scale is of an earlier date than the flute found at the Neanderthal campsite.

(C) The flute was made from a cave-bear bone and the campsite at which the flute fragment was excavated was in a cave that also contained skeletal remains of cave bears.

(D) Flutes are the simplest wind instrument that can be constructed to allow playing a diatonic scale.

(E) The cave-bear leg bone used to make the Neanderthal flute would have been long enough to make a flute capable of playing a complete diatonic scale


Answers:

48). OA - A
http://forum.prachipareekh.net/viewtopic.php?f=24&t=556

49). OA - E
http://forum.prachipareekh.net/viewtopic.php?f=24&t=138

Wednesday, February 18, 2009

CR Question 46, 47

46). For the past 13 years, high school guidance counselors nationwide have implemented an aggressive program to convince high school students to select careers requiring college degrees. The government reported that the percentage of last year's high school graduates who went on to college was 15 percent greater than the percentage of those who graduated 10 years ago and did so. The counselors concluded from this report that the program had been successful.

The guidance counselors' reasoning depends on which one of the following assumptions about high school graduates?


(A) The number of graduates who went on to college remained constant each year during the 10-year period.

(B) Any college courses that the graduates take will improve their career prospects.


(C) Some of the graduates who went on to college never received guidance from a high school counselor.


(D) There has been a decrease in the number of graduates who go on to college without career plans.


(E) Many of last year's graduates who went on to college did so in order to prepare for careers requiring college degrees


47). Frobisher, a sixteenth-century English explorer, had soil samples from Canada's Kodlunarn Island examined for gold content. Because high gold content was reported, Elizabeth I funded two mining expeditions. Neither expedition found any gold there. Modern analysis of the island's soil indicates a very low gold content. Thus the methods used to determine the gold content of Frobisher's samples must have been inaccurate.


Which of the following is an assumption on which the argument depends?


(A) The gold content of the soil on Kodlunarn Island is much lower today than it was in the sixteenth century.


(B) The two mining expeditions funded by Elizabeth I did not mine the same part of Kodlunarn Island.


(C) The methods used to assess gold content of the soil samples provided by Frobisher were different from those generally used in the sixteenth century.


(D) Frobisher did not have soil samples from any other Canadian island examined for gold content.


(E) Gold was not added to the soil samples collected by Frobisher before the samples were examined.


Answers:

Best approach for such questions is to negate the assumption and then look what effect this creates on the conclusion

46). OA - E

1st Premise: High school guidance counselors nationwide have implemented an aggressive program to convince high school students to select careers requiring college degrees

2nd Premise: The government reported that the percentage of last year's high school graduates who went on to college was 15 percent greater than the percentage of those who graduated 10 years ago and did so.

Conclusion:The counselors concluded from this report that the program had been successful.

Using deniel test: Many of last year's graduates who went on to college did not prepare for careers requiring college degrees - if this was true can we draw the conclusion that the program was successful - No, because then the very purpose of the program gets defeated(high school guidance counselors nationwide have implemented an aggressive program to convince high school students to select careers requiring college degrees), hence the program would have not been a success


47). OA - E

Using deniel test: Gold WAS added to the soil samples collected by Frobisher before the samples were examined.

If the above statement was true, can we draw the conclusion that method was inaccurate -- No, hence E must be the answer

Why not C:
Methods were different. So what? Does it prove or deny the conclusion that method was inaccurate? No ..hence ruled out.


Monday, January 19, 2009

CR Question 45

Nearly all mail that is correctly addressed arrives at its destination within two business days of being sent. In fact, correctly addressed mail takes longer than this only when it is damaged in transit. Overall, however, most mail arrives three business days or more after being sent.

If the statements above are true, which one of the following must be true?

A) A large proportion of the mail that is correctly addressed is damaged in transit

B) No incorrectly addressed mail arrives within two business days of being sent

C) Most mail that arrives within two business days of being sent is correctly addressed

D) A large proportion of mail is incorrectly addressed.

E) More mail arrives within two business days of being sent than arrives between two and three business days after being sent


Answer: D

OE:
This is a tricky question because it asks the test taker to come to a conclusion that is obviously false in real-life (but standardized tests aren't real life).
The question tells us that nearly all mail that is correctly addressed arrives within two business days. The only mail that doesn't arrive within two business days must be damaged mail and incorrectly addressed mail. Because we know that nearly all correctly addressed mail is not damaged, the fact that most mail arrives three business days or more after being sent can be read to indicate that there is a very large number of incorrectly addressed mail, which is answer (D).

A - incorrect - because the question states that 'overall, most mail arrives within three days,' indicating that a small amount of mail was lost.

B - incorrect - the passage contains no information to rule this possibility out.

C - incorrect - the passage tells us that if a piece of mail is correctly addressed that it will arrive within two days, assuming that there is no damage. But, if a large proportion of mail is incorrectly addressed (see D), then it is possible that (C) is not true since a large proportion is not correctly addressed.

E - incorrect - There is no evidence of this in the statement or way to deduce it.