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# PT4.S1.Q23 100 people use cocaine

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The debate comes down to B and C.

For B, I eliminated basing on the "average population." remember, the question stem never actually mentions what is true about the average population. We only know that if 100 ppl never smoked crack, only 5 would get falsely tested positive. but in 100 crackhead, 99 would get tested positive. Do we know the average number of crackhead among society? No. That would be something like in American society, there are on average 8 crackheads among 100 people. We don't have this information. So we cannot say that the flaw is applying the stats of average member to every member of the society, since there is no mentioning of what is the average.

C catches the flaw. My first reaction was that wait a minute, if the vast majority who got positive are confirmed crackheads, what if everyone doesn't smoke crack in this perfect society? Then according to the stem, 5 in every 100 ppl who never smoked crack will get tested positive, then you have the vast majority who got tested positives are not crackheads: they all got falsely tested positive and never smoked before. Well let's increase that to let's say there are an average of 7 crackheads among 100 people. Well still, the amount of crackheads are still not the vast majority of those tested positive. From this reasoning, we then know that we need to know how much people are actually crackhead in among the general population, then we can know whether the VAST MAJORITY of the people who test positive are crackheads. Let's say we are in NYC, and we have about 60 out of 100 on average are crackheads (maybe or maybe not exaggerated). Then the argument might actually make sense according to the 100 tested 99 positive stat. Without the average proportion of crackheads, we cant draw the conclusion about how many will get accurately tested positive in a society.

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• #### PT4.S1.Q23 - When 100 people who have not used cocaineHi All, Having a bit of trouble getting my head around this question. Originally chose B, but correct answer is C. Had a bit of a crack at it, an…

• Monthly Member
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is this rill

• Alum Member
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@lekSAT__ said:
is this rill

what is rill wtf

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@lekSAT__ said:
is this rill

I chuckled from just reading the title because I didn't anticipate this topic appearing on the test. I've never seen this question before. This PT is from 1992 so subject matter fits. The derogatory term doesn't appear in the stimulus.

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@LivinLaVidaLSAT said:

@lekSAT__ said:
is this rill

I chuckled from just reading the title because I didn't anticipate this topic appearing on the test. I've never seen this question before. This PT is from 1992 so subject matter fits. The derogatory term doesn't appear in the stimulus.

yea this is really old but took me a while to get it right and type it out to memorize. Thought the discussion button would just make a note to myself next thing I know was someone asking if this is a real question loll