With a record number of new companies starting up in Derderia and with previously established companies adding many jobs, a record number of new jobs were created last year in the Derderian economy. This year, previously established companies will not be adding as many new jobs overall as such companies added last year. Therefore, unless a record number of companies start up this year, Derderia will not break its record for new jobs created.
Which of the following is an assumption on which the argument relies?
(A) Each year, new companies starting up create more new jobs overall than do previously established companies.
(B) Companies established last year will not add a greater number of jobs overall this year than they did last year.
(C) This year, the new companies starting up will not provide substantially more jobs per company than did new companies last year.
(D) This year, the overall number of jobs created by previously established companies will be less than the overall number of jobs lost at those companies.
(E) The number of jobs created in the Derderian economy last year was substantially larger than the number of jobs lost last year.作者: 小宇宙2010 时间: 2011-5-12 21:14
New Job Created = Jobs created by "previously established companies" + Jobs created by "starup companies"
If you negate C, you have: This year, the new companies starting up will provide substantially more jobs per company than did new companies last year. If this is true, although no new jobs will be created by "old companies," it is possible that jobs created by "new companies" might exceed the total number of jobs created last yeart. Then the argument falls apart. So C is the necessary assumption.
In terms of math:
A = 100 (old companies) + 200 (new companies)
B = 99 (old companies) + x (new companies)
If the conclusion says that B<A, then x has to be less than 200 (last year's new job number).
C) unless a record number of companies start up this year, Derderia will not break its record for new jobs created:
Not A unless B: If A, then B; If not B, then not A.
The total new jobs created by new companies = number of new companies * average number of new jobs created in each new company. Even if the number of new companies drops or remains the same as last year, if the average number of new jobs per new company reaches a new height, the total number of new jobs might still be a record. C simply prevents that from happening.作者: yidiyuehans 时间: 2011-5-16 20:00
