请教一道逻辑题目

fpplpp · 发表于 2003-9-24 11:34:00

请问有谁可以讲解一下。谢谢。

Recent estimates predict that between 1982 and 1995 the greatest increase in the number of people employed will be in the category of low-paying service occupations. This category, however, will not increase its share of total employment, whereas the category of high-paying service occupations will increase its shares.

answer is A.In 1982, more people were working in low-paying service occupations than were working in high-paying service occupations.

谢谢。

dorbear · 发表于 2003-9-24 12:30:00

可以把题干和其他选项贴出来吗？

oliviading · 发表于 2003-9-24 23:40:00

正是因为1982年LOW-PAYING 的人数多于HIGH-PAYING的人数，尽管1982-1985年间LOW-PAYING的绝对人数增加大于HIGHPAYING的人数，但其增加的速度如果不及后者的话，其在总的雇佣人数中的比例还是会下降
不知这样解释是否清楚

miejue · 发表于 2003-9-25 00:04:00

呵呵，太巧了。。。。coincidentally, I am looking exact this question now....!!!

这题可以这么理解，假设原来低工资和高工资的数量一样，现在低工资增加的数量多于高工资的数量，则变动后的低工资的比率一定高。既然变动后低工资的比率不变，那原来低工资的人数一定更少。数学推导如下：

假设1982年低工资人数A，高工资人数B，1995年低工资人数为A+c, 高工资人数为B+c－n(因为高工资增加人数一定比低工资人数少，这里假设少n人)。
1982年低工资比率为A/A+B; 1995年该比率为(A+c)/(A+c+B+c-N). 由题意知两比率相同。合并等式后得B/A=1－n/c, 所以B/A一定小于1，即B
不过考试的时候这么一推，估计考完就可以去推长城了。。。。花5分钟推长城？死了算了！

[此贴子已经被作者于2003-9-25 0:15:47编辑过]

fpplpp · 发表于 2003-9-25 05:47:00

thank you very much for all your replies. now this question makes a lot of sense to me.

btw, i have to say sorry since i forgot to put up the complete question.

thanks again.

miejue · 发表于 2003-9-25 09:54:00

You are welcome to post any question illuse you at any time you wish here.

请教一道逻辑题目