In Wareland last year, 16 percent of licensed drivers under 21 and 11 percent of drivers ages 21-24 were in serious accidents. By contrast, only 3 percent of licensed drivers 65 and older were involved in serious accidents. These figures clearly show that the greater experience and developed habits of caution possessed by drivers in the 65-and-older group make them far safer behind the wheel than younger drivers are.
Which of the following is an assumption on which the argument depends?
Drivers 65 and older do not, on average, drive very many fewer miles per year than drivers 24 and younger.
Drivers 65 and older do not constitute a significantly larger percentage of licensed drivers in Wareland than drivers ages 18-24 do.
Drivers 65 and older are less likely than are drivers 24 and younger to drive during weather conditions that greatly increase the risk of accidents.
The difference between the accident rate of drivers under 21 and of those ages 21-24 is attributable to the greater driving experience of those in the older group.
There is no age bracket for which the accident rate is lower than it is for licensed drivers 65 and older.
情景:在W,16%的小于21岁的人和11%的21-24岁的人是在严重的事故中的。但是,只有3%的超过65岁以上的驾驶员是在严重事故中的。因此,这些数据表明,更多的经验和安全驾驶的习惯让老司机们更安全。
推理:提炼出前提和结论则有:
前提:6%的小于21岁的人和11%的21-24岁的人是在严重的事故中的。但是,只有3%的超过65岁以上的驾驶员是在严重事故中的。
结论:更多的经验和安全驾驶的习惯让老司机们更安全
显然地,前提是结果,结论在探究该结果产生的原因。因此本题为果因推理。
选题方式:由于本题问的是加强,所以答案选项应在将否定词去掉后断掉因果间的联系,或给出老司机事故率低的其它原因。
选项分析:
A选项:Correct. 超过65岁的司机不会每年开的路程比24岁或以前的司机要少。如果老司机们本来开的就少,那么其自然可以解释为什么老司机事故率低,这不是因为技术好,而是因为本来就开的少,出严重事故的概率自然低。
B选项:超过65岁的司机不会比18-24岁的司机占W市的司机比重更高。到底老司机占比多还是新司机占比多,均和事故率无关。
C选项:65岁或以上的司机比24岁或以前的司机更少在容易出事故的路段开车。本选项给出了老司机事故率低的另一个原因,即,开的路更安全。但由于本题问的是假设,不是削弱,因此本选项是错误的。
D选项:21岁以前的司机和21-24岁的司机出事故率的区别可以被归因为经验。本题讨论的是65岁的老司机和24岁以前的小司机的事故率区别的原因,不是24岁和21岁的区别。
E选项:没有比65岁过以上的司机出事故率更低的年龄段了。本选项和为什么事故率低无关。
看到百分比就要想到总数。
两组数据要具有可比性,在数据规模上要一致。
论点:老年组比年轻组事故率低是因为经验丰富。
A选项说的是两组人的人均里程数差不多,这样来比较事故率就有意义了。
B选项可以这样来理解,虽然老年组和年轻组人数差不多,但是开车上路的时候少,事故率就低了,不能支持论点事故低是因为经验足。
登录 或 注册 后可以参加讨论