ten different items are for sale in a store,and each is sold at a different price.the average price of these 10 items is $165.if the prices of all the items are changed,will the average price increase? (1)the five most expensive itenms will increase in price by 10% (the five least expensive items will decrease in price by 10%
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刚刚又想了想,条件一和条件二单独时都不充分,因为都只说了5个ITEM的情况而没说其他的增减情况,
而如果TOGATHER的话,也不充分,因为不知道whether the increment of these five most expensive items is greater than that of the five least expensive items.
所以这道题应该是选E吧?
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但是楼主还是很困惑如果一道题出现我一开始描述的情况要怎么选啊!!!
拿这道题来说,假如条件现在是
(1)the five most expensive items will increase in price by 10% while the others remain the same (2)the five least expensive items will decrease in price by 10% while the others remain the same