Q14 - In 1980, Country A had

[wayne_palmer10]

This is a necessary assumption question. Since the stimulus used concrete numbers, I was looking for an answer choice that did the same. I ultimately guessed with (D) but can't seem to figure out why it's correct.

[dan]

I think your instincts were good (to focus on the numbers). Here's an explanation that might help:

In 1980, the per capita GDP of Country A was $5,000 higher than that of the European Economic Community (EEC). In 1990, the per capita GDP of Country A was $6,000 higher than that of the EEC. The trap is to assume that Country A’s number went up. However, this is not necessarily the case. Take the following analogous example:

Candy bar consumption yesterday:
Me: 9
You: 4

Candy bar consumption today:
Me: 9
You: 3

In this case, the difference was 5 yesterday and 6 today. However, my consumption did NOT increase. Yours simply decreased.

In other words, the growth in the difference between GDP’s could be accounted for by a decrease on the part of the EEC instead of an increase on the part of Country A. The author of the argument assumes that Country A’s per capita GDP increased (leading to a rise in the standard of living).

Answer (D), the correct answer, expresses this assumption in a very subtle way. In order to say, with certainty, that Country A’s per capita GDP increased, we need to assume two things: (1) that the EEC’s per capita GDP did not decrease by exactly $1,000, and (2) that the EEC’s per capita GDP did not decrease by more than $1,000. Let’s look at both cases:

1980 per capita GDP’s:
Country A: $15,000
EEC: $10,000

1990 per capita GDP’s:
Country A: $15,000
EEC: $9,000

As we can see, if the EEC’s per capita GDP goes down by exactly $1,000 to get to a difference of $6,000, then Country A’s must stay the same (Country A does NOT increase!).

1980 per capita GDP’s:
Country A: $15,000
EEC: $10,000

1990 per capita GDP’s:
Country A: $14,999
EEC: $8,999

If the EEC’s per capita GDP decreases by more than $1,000 ($1,001 in this case), we see that Country A’s per capita GDP must go down as well in order to get a $6,000 difference. In summary, in order to conclude with certainty that Country A’s per capita GDP went up, we must assume:

(1) EEC’s did not go down by exactly $1,000.
(2) EEC’s did not go down by more than $1,000.

The correct answer need not express both of these, but each of them is required to make the argument valid. Answer (D) expresses the second assumption.

(A) is out of scope. A comparison of populations is irrelevant. Per capita GDP figures already account for any differences in population.
(B) is irrelevant. A decrease in the EEC’s standard of living tells us nothing about whether Country A’s per capita GDP went up.
(C) is out of scope. The standard of living for EEC member countries is irrelevant.
(E) is out of scope. The individual per capita GDP’s for EEC member countries tell us nothing about whether Country A’s per capita GDP went up.

Hope that helps!

dan

[nazu.s.shaikh]

This is more of a question regarding attacking an assumption question rather then this question itself but is the reason why answer D is the correct answer because in the stimulus the GDP increase for Country A was explained for both 1980 & 1990 ( inflation) while there is no connection/explanation of the GDP for the EEC ? With that in mind when answering an assumption question should we look for a missing link in the stimulus ( in this case there was no mention of the EEC's GDP other than it was so and so much higher/lower than Country A's GDP)

The reason I ask this is because when I was doing POE of the answers I ended up with B & D as my final answers and was leaning towards B as my answer mainly because of the last part in the stimulus which says " the average standard of living in Country A must have risen between 1980 and 1990"

In comparison to the rest of the EEC's standard of living, Country A's would have a higher standard of living because of its higher GDP. Like the author would have assumed that EEC's standard of living wasn't as great as Country A's was.

[ManhattanPrepLSAT2]

For all assumption questions, it is useful to both
a) look out for missing links and anticipate what you might see in the answer choices
b) use POE and stay open-minded about the role the right answer will play.

This is a necessary assumption question, so that means that the right answer is something that
a) must be true in order for the argument to be true but
b) doesn't, by itself, have to make the argument perfectly sound.

Your process seems fine, and (B) and (D) are certainly the most attractive answers.

The conclusion of the argument states that Country A must have a higher standard of living relative to what it was in 1980, not relative to other countries in the EEC. Therefore, it neither helps nor hurts our cause if the standard of living decreased in other countries. Keep in mind that, just based on this argument, a falling standard of living does not indicate falling GDP. (B) does not have to be correct in order for the conclusion to be sound.

The gap in this argument has to do with the assumption that Dan highlighted -- the author is assuming an increase in one number (GDP of Country A) because of a change in its relation to another number (GDP of Country B), and we need to address this issue. (D) does this in the clever way Dan described.