I chose A and correct answer is B. I rember this problem form OG11 (not the answer though) so I went there to check the explanation but it didnt convince me at all. I guess I dont understand it. I think B is "so obvious" it does not say anything new.




Any comments about this one?

Thanks

Hi, Luci - sorry this one got lost in the madness of the past week!

Summary:
3% of all equipped with detectors
33% of vehicles caught speeding equipped with detectors
Conclusion: drivers who use detectors are more likely to speed regularly than those who don't

Author has made a leap between speeding only occasionally and getting (unluckily) caught vs. speeding regularly - but the rest of the argument does not actually mention anything about the frequency of speeding of various groups. It may be obvious that the more often you speed, the more chances you have to get caught - but the argument does not spell this out.

Choice A does not address author's conclusion - he's contending that drivers who choose to use detectors do so because they plan to speed regularly. This choice says that whether someone has a detector has a bearing on whether s/he gets caught - which may be true in the real world, but it does not answer this question.

Choice B addresses this leap that the author makes about the frequency of speeding. If drivers who are ticketed are likely to exceed the speed limit regularly, then the 33% of vehicles caught speeding with detectors will fall into this category of people who are more likely to speed regularly. Remember, again, that it may be obvious that the more often you speed, the more likely you are to get caught - but the argument doesn't literally spell it out, and that's the point. The author is just assuming this point is true without spelling it out.

Can someone explain why D is incorrect?

Thanks.

hey -

d is incorrect because its content is irrelevant to the content of the passage.

the passage talks in terms of percentages of the number of VEHICLES ticketed - not percentages of the total number of tickets. therefore, even if certain vehicles were ticketed multiple times, nothing in the argument would change (because one vehicle still counts as one vehicle, even if it is pulled over multiple times).

also note that you're looking for an ASSUMPTION that is REQUIRED by the passage. if you pick an answer like d - which is clearly not REQUIRED by the argument, even if you don't immediately see why it's irrelevant - that probably means you aren't reading the question prompt correctly.