[問題] 陳向東數學2題

看板GRE (GRE入學考試)作者 (Q仔)時間11年前 (2014/09/27 14:54), 編輯推噓1(106)
留言7則, 2人參與, 最新討論串1/1
大家好: 最後兩題關於陳向東數學的問題,因為後面練習部分沒有詳解... 多次打擾, 不好意思! P207. 13. A certain five-number committee must be assembled from a pool of five women- A, B, C, D, E, and three men-X, Y, Z, what is the probability that the committee will include B, C, E, Y, and Z? Ans: 1/30 P274. 12. Table: House price Number of Houses $ 100,000-133,000 12 $ 134,000-166,000 25 $ 167,000-199,000 8 Tha table show the distribution of prices of 45 houses for sale in a certain region. Select two of following choices and place them in the blanks below the resulting statment is true. $175,000 $185,000 $190,000 at most $42,000 at least $57,000 If the highest price of the 45 houses is _______, then the range of the prices of the 45 houses is_______. Ans: the first blank is 190,000, and the second blank is at least $57,000 這題應該很簡單但我不知道怎麼求出答案, 可能題目沒看懂。 謝謝大家! -- ※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 180.177.48.63 ※ 文章網址: http://www.ptt.cc/bbs/GRE/M.1411800862.A.A41.html

09/27 16:21, , 1F
第一題是不是有少加女性必須要選兩人,男性選一人?
09/27 16:21, 1F

09/27 16:22, , 2F
第二題只能用反推的, 最後一格一定是後兩個
09/27 16:22, 2F

09/27 16:22, , 3F
但最少的 17500-13300 恰為 42000,所以反推就是不
09/27 16:22, 3F

09/27 16:23, , 4F
可能,所以最後一格一定是至少 57000
09/27 16:23, 4F

09/27 16:23, , 5F
57000+133000就是190000
09/27 16:23, 5F

09/27 16:24, , 6F
第三行 175000-133000
09/27 16:24, 6F

09/30 13:59, , 7F
第一題沒有規定女性必須選2人, 男性選1人耶...
09/30 13:59, 7F
文章代碼(AID): #1K9byUf1 (GRE)
文章代碼(AID): #1K9byUf1 (GRE)