[問題] 猴哥數學問題

看板GRE (GRE入學考試)作者 (楊麗花)時間15年前 (2011/05/25 20:25), 編輯推噓1(102)
留言3則, 1人參與, 最新討論串3/3 (看更多)
裡面的第10題 If 55 percent of a group of people have browm hair and 80 percent of the same group do not have red hair, what fraction of those who do not have brown hair have red hair? 這題的答案是C 4/9 請問是怎麼算出來的? -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 140.114.20.143

05/25 20:50, , 1F
Q: 再沒b中帶r的比例是多少
05/25 20:50, 1F

05/25 20:51, , 2F
20/45= 4/9 !
05/25 20:51, 2F

05/25 20:52, , 3F
(100-80)/(100-55)
05/25 20:52, 3F
文章代碼(AID): #1DtFK-2g (GRE)
文章代碼(AID): #1DtFK-2g (GRE)