Prep 2-40 不懂啊不懂

barila

40.   (32847-!-item-!-188;#058&007552)

    

 

    

A recent report determined that although only
three percent of drivers on Maryland highways equipped their vehicles with
radar detectors, thirty-three percent of all vehicles ticketed for exceeding
the speed limit were equipped with them. 
Clearly, drivers who equip their vehicles with radar detectors are more
likely to exceed the speed limit regularly than are drivers who do not.

    

 

    

The conclusion drawn above depends on which of the
following assumptions?

    

 

    

(A) Drivers who equip their vehicles with radar
detectors are less likely to be ticketed for exceeding the speed limit than are
drivers who do not.

    

(B) Drivers who are ticketed for exceeding the
speed limit are more likely to exceed the speed limit regularly than are
drivers who are not ticketed.

    

(C) The number of vehicles that were ticketed for
exceeding the speed limit was greater than the number of vehicles that were
equipped with radar detectors.

    

(D) Many of the vehicles that were ticketed for
exceeding the speed limit were ticketed more than once in the time period
covered by the report.

    

(E) Drivers on Maryland highways exceeded the
speed limit more often than did drivers on other state highways not covered in
the report.

答案是B，我一点头绪都没~~~thanks for help~~~ 

morningjay

装雷达的车主只占总数量的3%

而在被开罚单的人数比例中装雷达的人有33%

由此推出了装雷达的人regularly更容易超速。

那这样个推论的前提是什么呢：是被开罚单的人还是继续REGULARLY超速。

好象我也一知半解。。是这么分析吗？

morningjay

我觉得被开罚单的人数比例中装雷达的人有33%，这个比例高于3%是关键。由于这个不合比例而的出的结论是装雷达的人更容易超速。

而支撑这个结论的就是2个比例的不对称。而如果被开单的人还是likely,regularly超速的话。就保证了这个不对称的比例的继续存在。。

[此贴子已经被作者于2008-11-12 5:43:37编辑过]