#21 - Engineer: Air bags in automobiles occasionally cause

[Administrator]

Please post your questions below! Thank you!

[Retteye1]

Hello, can you help me understand why B is wrong? I understand why A is right, but B also seems right. It seems like the system could fail in ways other than the air bags accidentally inflating. What if the system failed but didn't inflate the air bag? Wouldn't that disprove that it will only make the airbag problem worse?

[Jeremy Press]

Hi Retteye,

Be careful with answers in Flaw questions that begin with the phrase "takes for granted," or "presumes without providing justification." Those answers are describing a flawed assumption, "takes for granted" being a synonym for "assumes" on the LSAT. Often what's wrong with these answers is that the facts they're describing aren't truly necessary to the author's argument, and therefore aren't actually being assumed by the author. If the fact in the answer isn't being assumed by the author, we have to eliminate the answer (because that answer inaccurately describes the argument).

Many times what happens with such answers is they sketch out a fact that's very strong and broad, much stronger and broader than what the author really needs to assume. That's what's happening with answer choice B here. Our author isn't assuming that any (i.e. every) failure will cause accidental inflation. Our author is assuming that the new systems will have more failures that will probably cause more accidental inflations. See that quantitative difference (affecting both the number of failures and the certainty that they will cause inflations)? That's the reason answer choice B is too strong to be a necessary assumption of the argument. And that's the reason we have to get rid of answer choice B.

Watch out for that on Flaw questions with "takes for granted" (or "presumes") style answer choices. Make sure that assumption fits the quantitative needs of the argument and doesn't go beyond them. If it goes too far, it's wrong.

I hope this helps!

[theamazingrace]

Hi Retteye,

Be careful with answers in Flaw questions that begin with the phrase "takes for granted," or "presumes without providing justification." Those answers are describing a flawed assumption, "takes for granted" being a synonym for "assumes" on the LSAT. Often what's wrong with these answers is that the facts they're describing aren't truly necessary to the author's argument, and therefore aren't actually being assumed by the author. If the fact in the answer isn't being assumed by the author, we have to eliminate the answer (because that answer inaccurately describes the argument).

Many times what happens with such answers is they sketch out a fact that's very strong and broad, much stronger and broader than what the author really needs to assume. That's what's happening with answer choice B here. Our author isn't assuming that any (i.e. every) failure will cause accidental inflation. Our author is assuming that the new systems will have more failures that will probably cause more accidental inflations. See that quantitative difference (affecting both the number of failures and the certainty that they will cause inflations)? That's the reason answer choice B is too strong to be a necessary assumption of the argument. And that's the reason we have to get rid of answer choice B.

Watch out for that on Flaw questions with "takes for granted" (or "presumes") style answer choices. Make sure that assumption fits the quantitative needs of the argument and doesn't go beyond them. If it goes too far, it's wrong.

I hope this helps!

I think I understand your explanation. Can you please reword answer choice A? I don't really get what it is saying.

Thanks

[KelseyWoods]

Hi theamazingrace!

To make sure we understand answer choice (A), let's first breakdown the argument:

Conclusion: the new computer control systems will probably only make the problems with accidental air bag inflation even worse
Premise: the new air bag systems are more complex and the more complex such a system is, the more ways there are in which it can fail

So the author is saying that just because the new systems have more different ways in which they can fail, that means that the problem with air bag failure is going to get worse (i.e., there will be more air bag failures).

Answer choice (A) describes the flaw the author has made. The author has failed to address the fact that just because there are more ways in which something can fail, that doesn't necessarily mean that something is more likely to fail.

Hope this helps!

Best,
Kelsey

[cjtoon]

Answer choice A is correct rather than answer choice B because it is the actual flaw in the argument. However, B is enticing because it, if assumed, would actually justify/'make valid' the argument.

In other words, B could be an answer in a hypothetical justify/sufficient assumption variation of this question. Although the answer to a flaw question may actually be a statement that if assumed would make the argument valid, be careful to always prioritize picking the actual flaw and not the gap in logic.

[Jeff Wren]

Hi cjtoon,

Answer B doesn't actually justify/make the argument valid because the flaw described in Answer A is still present.

Answer B is stating that if a failure in an air bag's computer system occurs, then the air bags will inflate accidentally. However, the likelihood of any given type of failure must still be taken into account in order to determine whether or not the new computer system will result in more accidental air bag inflations.

Here's an example with some unrealistic/exaggerated figures to illustrate the point.

Imagine the old system had 1 way that it can fail, and that happened 1 in every 10,000 times.

The new system has 3 ways that it can fail, but each of those happens 1 in every million times.

Let's also imagine that Answer B is true, and every failure causes the air bags to accidentally inflate.

Here, even though the new system has more ways to fail, the actual probability of the air bags accidentally inflating is still lower under the new system. In other words, a higher number of very low probability events can still be less likely than a lower number of higher probability events.

[aspiringdefender]

I was stuck between A and E for this question, and I ultimately chose the wrong answer, E. After reading it again, however, I can see why A is a much better answer, but I would like it if someone could verify my interpretation as to why E is a worse answer.

E is a worse answer because it does not omit the possibility that accidental air bag inflations still cause many injuries. It is true that they can also prevent injuries, but the fact that they still, equally, can cause many injuries "cancels out" the amount of injuries that they prevent, and thereby does not give any "net" amount of advantage. Answer A is much stronger, simply because it attacks the reasoning in the argument. If the system's failing does not actually increase the number of ways in which it fails, that more definitively attacks the argument.

How is my rationale for ruling out E? Am I missing anything?

[Dana D]

Hey aspiringdefender,

Answer choice (E) essentially restates something we were already told in the stimulus - airbags occaisionally cause injuries. It's inferrred that they prevent more injuries than they cause, so this answer choice isn't really giving us new information. The bigger issue with this answer choice is that it doesn't have anything to do with the flaw in the reasoning.

I don't think the stimulus or this answer is implying that air bags ever cause as many injuries as they prevent, eliminating their "net" benefit. But even if they did, the flaw in the passage is the author's assumption that more manners of ways in which failure can occur will directly correlate to an increase in the number of failures that will occur (accidents via airbag). But that's just not true.

Hope that helps!