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PrepTest 73, Logical Reasoning 2, Question 18


Question 18, when a question wants the flawed pattern of reasoning that's similar to another pattern of reasoning, that's a parallel flaw question. For parallel flaw questions, we're gonna go into the answer choices looking for something that has the same bad reasoning as the original argument. With parallel flaw questions, it's often easiest to start out by identifying the flaw.

But of course, to do that you have to understand the argument. So here, the argument's conclusion is at the end, it'll probably rain in the valley within the next week. We get three pieces of evidence to prove that, first, so far this summer there hasn't been any rain in the valley. Second, usually there is some rain there every summer.

And then our only piece of evidence that has the evidence keyword since. So since only one week of summer is left. That's our argument, it's probably gonna rain because it usually rains in the summer. Hasn't rained so far this summer and there's not much summer left. Now the flaw here doesn't have a fancy Latin name.

It's sort of a version of the sportscaster cliche that someone is due for a hit. So say that a hitter goes through a long dry spell, and the longer they fail to hit ,the baseball announcer says, well, clearly he's due for a hit. It's probably gonna hit any day now, it's kind of a joke. The more they fail to hit, the more they say that they're due for a hit. When probably if they keep not hitting, it's because they're actually not very good.

So here they're saying we're due for rain, even though we've had a whole summer with no rain. Why would this last week be more like the summers before and not more like the summer that it's actually attached to? So that's going to be the flaw that we'll look for in the answer choices. But remember, for an argument to be parallel, it has to have the same kind of conclusion, the same kind of evidence and use the evidence in the same way.

So any of those if it violates, we could get rid of it without considering whether it's got the same flaw. So answer choice A, we have Aisha who is proofreading a journal, she's almost done. And there are two errors here in this answer choice, or at least two things that make it not the flaw that we started with. First, it says that there are sometimes a few errors in her journal.

But our evidence was that there's usually a few inches of rain, not sometimes but most of the time. And second, it says that there may be errors in the pages but the original was stricter than that. There will probably be rain, not just that there may be rain, so A is not our answer. Answer choice B, well, it's got a couple errors too but the main one is, it's concluding the opposite of what our original argument concluded.

There are probably no errors, but it was probably going to rain. So answer choice B doesn't match, answer choice C does match. Its conclusion, there are probably errors in the pages she hasn't yet checked in the issue of the journal. It's probably gonna rain in the valley within the next week. Its first piece of evidence, so far this summer there's been around the valley matches up with she's finished proofreading so far and has encountered no errors.

Usually there's rain there every summer, on average, there are a few errors in an issue of the journal. And there's only one week of summer left, there's only two pages of this journal left. Each piece corresponds the original, it's got the doofer flaw, it is our answer. So two wrong answers remain, D is wrong.

For the same reason that B was wrong. It's saying that there will probably be no errors, but the original argument was it's probably going to rain. And then answer choice E, well she's finished now, the summer isn't finished. So the only answer that's parallel is answer choice C.

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