※ 引述《slin (slin)》之铭言： : 23. 1653-!-item-!-187;#058&000843 : At least 100 students at a certain high school study Japanese. If 4 percent : of the students at the school who study French also study Japanese, : do more students at the school study French than Japanese? : (1) 16 students at the school study both French and Japanese. : (2) 10 percent of the students at the school who study Japanese also : study French. : 答案选 B : 我不懂的是选项二中,who study Japanese also study French 跟题目的study French : also study Japanese是不一样的意思吗?? 题目中的意思为"学校里修习法文的人"中有4%也修日文 选项二的意思为"学校里修习日文的人"中有10%也修法文 这个4%的人数与10%的人数其实是一样多的(也就是两者都修的人数，设为x) 所以学校中修法文的人数为 x / 4% = 25x 学校中修日文的人数为 x / 10% = 10x 答案为B A应该就不用讲了 : 35. 3076-!-item-!-187;#058&003114 : If p and n are positive integers and p > n, what is the : remainder when p^2 - n^2 is divided by 15 ? : (1) The remainder when p + n is divided by 5 is 1. : (2) The remainder when p - n is divided by 3 is 1. : 答案选 E 没有想到很直接的方法 所以我用列举的来试验 p + n = 6 . 11 . 16 . 21 . 26 ........ p - n = 4 . 7 . 10 . 13 . 16 ....... 逐一试验 找到 p = 10 n = 6 这一种解 (p^2 - n^2) / 15 的余数为4 另找到 p = 14 n = 7 另一解 (p^2 - n^2) / 15 的余数为12 无法符合 所以选E 若有错请指正 谢谢 --

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