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UID600113在线时间 小时注册时间2011-1-25最后登录1970-1-1主题帖子性别保密 
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| 17.    1329-!-item-!-187;#058&000662 Six countries in a certain region sent a total of 75 representatives to an international congress, and no two countries sent the same number of representatives.  Of the six countries, if Country A sent the second greatest number of representatives, did Country A send at least 10 representatives?
 
 (1)  One of the six countries sent 41 representatives to the congress.
 
 (2)  Country A sent fewer than 12 representatives to the congress.
 1)當有一個地區是41, 表示剩下的5個區域=75-41=34
 故41的那個區域就會是greatest
 當A=9時,這34可以分配給剩下的區域 EX: (9,8,7,6,4) 符合題目要求 但A小於10
 當A=11時,則可分配成(11,8,7,6,2) 符合題目要求 但A至少等於10
 所以(1)不充分
 
 不明白为什么A-11了,其实也就是at least 10了呀,怎么解释还说不充分?
 不明白为什么
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