※ 引述《slin (slin)》之銘言： : 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. : 答案選 B : 我不懂的是選項二中,who study Japanese also study French 跟題目的study French : also study Japanese是不一樣的意思嗎?? 題目中的意思為"學校裡修習法文的人"中有4%也修日文 選項二的意思為"學校裡修習日文的人"中有10%也修法文 這個4%的人數與10%的人數其實是一樣多的(也就是兩者都修的人數，設為x) 所以學校中修法文的人數為 x / 4% = 25x 學校中修日文的人數為 x / 10% = 10x 答案為B A應該就不用講了 : 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. : 答案選 E 沒有想到很直接的方法 所以我用列舉的來試驗 p + n = 6 . 11 . 16 . 21 . 26 ........ p - n = 4 . 7 . 10 . 13 . 16 ....... 逐一試驗 找到 p = 10 n = 6 這一種解 (p^2 - n^2) / 15 的餘數為4 另找到 p = 14 n = 7 另一解 (p^2 - n^2) / 15 的餘數為12 無法符合 所以選E 若有錯請指正 謝謝 --

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