mun23 wrote:
In the city of Cantville, a high school earns the “Young Women in Science” award for a given year if at least ten of its female students participate in that year's state science exposition. Last year, 80 percent of all high schools in Cantville's District 1 earned this award, while only 63 percent of all high schools in the city's District 2 earned the same award. Furthermore, these percentages have remained at or near those respective levels throughout the entire twelve years since the award was instituted. It is clear, then, that the high schools in District 1 do a better job of encouraging girls to pursue science than do the high schools in District 2.
Which of the following is assumed in the argument above?
(A)Students in District 1 have more free time to pursue science projects than do students in District 2.
(B)The overall population of District 1 is not substantially larger than that of District 2.
(C)The average high school in in District 2 does not have more students than does the average high school in District 1.
(D)District 1 does not have significantly fewer all-male high schools than does District 2.
(E)School is the primary source of encouragement for students' pursuit of science.
Need detail explanation................
Frankly, all explanations above are really good. This question is NOT EASY at all. If you don't read it carefully, you may pick right answer by using POE, but I bet you did not understand deeply the idea that the GMAT makers want to convey in the question.
First of all, this is assumption question regarding percentage, specifically, defender assumption (if you're interested, read
Power Score CR Bible).
The most important thing here is that you must show
absolute value is different from percentage value. That's the KEY.
Let examine the question:Premise: D1 has 80% high schools earned award
Premise: D2 has 63% high schools earned award.
Conclusion: D does better than does D2 of encouraging girls to pursue science.
We have
two different cases here:(1)
DIFFERENT ABSOLUTE VALUES: D1 & D2 have different the number of schools.
(2)
SAME ABSOLUTE VALUES: D1 & D2 have the same number of high school;
This is the case in the question.
For case (1): the number of schools in D1 & that of D2 are different.The conclusion above is correct only if
The number of high schools in D1 is not fewer than that of D2. If No, the conclusion is broken.
For instance, if D1 has 100 high schools, 80% = 80 schools had award. But D2 has more, 200 high schools for example, 63% = 126 schools had award. Yeah, we cannot say D1 did better job than did D2. So the conclusion is not hold.
But this case is
TOO OBVIOUS and normally not considered in hard GMAT question.
For case (2): the number of schools in D1 & that of D2 are the same.Let assume:
The number of high schools = the number of NON-GIRL schools (all-male) + the number of GIRL INCLUDED schools. So, we only can conclude D1 did better job if its number of Girl included schools is
EQUAL or SMALLER than that of D2. If NO, review the example in case 1 above.
It also mean THE NUMBER OF NON-Girl SCHOOLS (all-male) OF D1
IS NOT FEWER THAN THAT OF D2.
That's exactly what answer D says.
Hope it's clear.
Regards.