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【OG20-P288-401题】
A group consisting of several families visited an amusement park where the regular admission fees were ¥5,500 for each adult and ¥4,800 for each child.Because there were at least 10 people in the group, each paid an admission fee that was 1 0% less than the regular admission fee. How many children were in the group?
(1) The total of the admission fees paid for the adults in the group was ¥29,700.
(2) The total of the admission fees paid for the children in the group was ¥4,860 more than the total of the admission fees paid for the adults in the group.
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人数A+C≥10→价格A:5500*90%=4950;C:4800*90%=4320
条件1:4950A=29700→A=6→C≥4,不充分
条件2:4320C-4950A=4860→48C-55A=54,不充分
1+2:A=6,C=8,充分
题目讨论 (7条评论)

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637298zxft
这题没看到at least反而省事了 答案是一样的哈哈
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0 回复 2021-10-24 15:16:58
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贾思敏
坑1:at least 10 people in the group 是A+C大于等于10 坑2:each paid an admission fee that was 1 0% less than the regular admission fee 不管是大人还是小孩的票价,都是乘以(1-10%),也就是乘以90%
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0 回复 2021-09-25 18:02:34
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Lori88
看错题了,以为就10个人
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0 回复 2021-08-10 23:58:49
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你这只猪
方程联立求解吧
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0 回复 2020-06-08 14:46:25
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园园爱吃肉
看错题了,以为就10个人。。。
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0 回复 2019-11-30 16:33:42
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hannahyz
需要解决的问题是:48C-55A=54是否有唯一解(在A+C>10,A、C均为正整数的情况下) 48*C-54=55*A 化成:6(8*C-9)=5*11*A 因此8*C-9 需要被55整除,A 被6整除。8C-9和A可以按比例无限扩大,比如 8C-9=55,A=6 8C-9=550,A=60 因此该二元一次不定方程没有唯一解,不充分。
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0 回复 2019-09-17 11:00:02
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cbc021
注意理解题意:因为团体成员超过10人,成年人和孩子的门票费都是标价的90%。
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0 回复 2018-02-21 13:31:24