题库搜索>问题求解PS-12650
At a garage sale, all of the prices of the items sold were different. If the price of a radio sold at the garage sale was both the 15th highest price and the 20th lowest price among the prices of the items sold, how many items were sold at the garage sale?
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价格都不一样
Radio是低15个最高的价格，也是第20个最低的价格；问有多少items?
15前面有14个比他低的item;15后面有比他高的19个item
所以：14+1+19=34
这就是一个排序问题，注意不要重复
狼狼狼
Radio 在低价格的集合，有15个元素； 在高价的集合种有20个元素。整个集合就有15+20-1 个元素 （Radio 是两个集合的交集，重复计算了，遂减一）
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2020-05-22 10:08:24
1271614zenmw
这题意思是ratio既是15th也是20th，
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2019-11-18 00:19:04
171348jp
不要重复！！！！！
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2019-09-05 16:38:30
水蜜桃味的秋葵
没有明白讲解，求大神详细说明。
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2019-03-27 10:42:12
Kath1230
这是啥题 完全没看懂 题目又没有说从小到大排列 而且也没说15后面的item就比它低啊。。。
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2019-01-12 23:35:03
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