标题: jj上的一题,求解 [打印本页] 作者: kaitohuang 时间: 2011-3-21 08:45 标题: jj上的一题,求解 In the years following an eight-cent increase in the federal tax on a pack of cigarettes, sales of cigarettes fell ten percent. In contrast, in the year prior to the tax increase, sales had fallen one percent. The volume of cigarette sales is therefore strongly related to the after-tax price of a pack of cigarettes.
The argument above requires which of the following assumptions? A.During the year following the tax increase, the pretax price of a pack of cigarettes did not increase by as much as it had during the year prior to the tax increase. B.The one percent fall in cigarette sales in the year prior to tax increases was due to a smaller tax increase. C.The pretax price of a pack of cigarettes gradually decreased throughout the year before and the year after the tax increase. D. For the year following the tax increase, the pretax price of a pack of cigarettes was not eight or more cents lower than it had been the previous year. E.As the after-tax price of a pack of cigarettes rises, the pretax price also rises. 作者: kaitohuang 时间: 2011-3-21 09:01
D的选项是什么意思?作者: sdcar2010 时间: 2011-3-21 10:18
It is a math question. The total sales = price of a single pack * number of packs sold.
When the sales is down, it could be caused by either the price drop or decrease in number of packs sold.
D makes sure the former did not happen, thus keeps the argument alive.作者: kaitohuang 时间: 2011-3-21 11:31
I got it. Thanks a lot.