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标题: 请教一道DS的题 关于不等式 [打印本页]

作者: 问答者你好吗    时间: 2017-12-8 23:00
标题: 请教一道DS的题 关于不等式
Each employee of Company Z is an employee of either division X or division Y, but not both. If each division has some part time employees, is the ratio of the number of full-time employees to the number of part-time employees greater for division X than for Company Z?

(1) the ratio of the number of full time employees to the number of part-time employees is less for division Y than for Company Z

(2) More than half of the full-time employees of Company Z are employees of Division X, and more than half of the part-time employees of Company Z are employees of Division Y


答案是D 两个分别都可以


有谁可以解释一下吗?特别是为什么第二个是可以得?谢谢!

作者: 一抹斜阳    时间: 2017-12-15 15:30
顶楼主!               
作者: hansoncheng    时间: 2019-6-24 14:35
设 X部门里的 part-time p1 ,full-time f1
    Y部门里的 p2 f2

问的是
f1/p1 > (f1+f2)/(p1+p2) 吗
化简得 f1p2 > f2p1

条件1:f2/p2 > (f1+f2)/(p1+p2)  化简得 f1p2 > f2p1  充分
条件2:f1 > f2 , p2 > p1 两式相乘得 f1p2 > f2p1 充分


我上来也懵了 把整个公司得情况也用未知数表达出来 之后就越算越乱

作者: 行素    时间: 2019-6-28 13:01
hansoncheng 发表于 2019-6-24 14:35
设 X部门里的 part-time p1 ,full-time f1
    Y部门里的 p2 f2

确实不太好表达,字母一大推好容易抄错,是不是赋值法会容易点?




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