标题: 这题应该选B吧？！ [打印本页] 作者: frankzhiwei 时间: 2010-12-11 20:58 标题: 这题应该选B吧？！ Last August the XT chainof gasoline stations had a temporary sales promotion in effect. In the promotion,any customer who made a purchase of ten or more gallons of gasoline wasentitled to a free car wash. For the month of August, XT experienced a tenpercent increase in gasoline sales as compared to sales in August the previousyear, so evidently the promotion was successful as a means of boosting sales. In evaluating theargument, it would be most helpful to answer which of the following? A. In the areas in which XT’s gasoline stations operate, howdid total combined gasoline sales for all gasoline stations last August comparewith sales for the previous August? B. Was the money that XT earned from the increase in gasolinesales enough to offset the cost of providing free car washes during thepromotion? C. Were there any customers who bought ten or more gallons atan XT gasoline station during the promotion who would have or more gallons atan XT gasoline in lower quantities, but more frequently, if the promotion had not been in effect? D. Did XT or any of its gasoline stations have to pay otherbusinesses to provide the car washes that customers were offered in thepromotion? E. Are XT’s gasoline sales in August usually significantlyhigher than one twelfth of XT’s annual gasoline sales?
本人选的是B，答案是A，为啥呀，求解释~~作者: sdcar2010 时间: 2010-12-12 09:34
If the total combined gaoline sales for all stations increased 10% this year over last year, then the 10% increase observed by the XT chain is simply a general trend for the whole region, not the direct result of it car wash promotion.
This is a typical alternative causation problem. If two things A and B happened together, there are multiple possibilities: A causes B, B causes A, another C causes both A and B, another D instead of B causes A.