※ 引述《amateurptt (剩自己了...)》之铭言： : ========================================================================= : 3. A certain taxi company charges $3.10 for the first [?] of a mile : plus $0.40 for each additional of a mile. What would this company : charge for a taxi ride that was 8 mile long? : 我的解法如下,请各位帮我看哪有出问题 : 3.10 + 7*0.40 但是与答案差相当多,我看错题目吗? mthe first [?] of a mile 总觉得少了些什麽 条件不够 : ============================================================================ : 4.In a stack of boards at a lumber yard, the 20th board counting from : the top of the stack is immediately below the 16th board counting from : the bottom of the stack. How many boards are in the stack? : (D)34 : ans:D 想请问解题思路 一个堆叠 从上数来 第20个 会比从下面数来 第16个还低 (immediately below) Top Bottom 1 2 3 4 5 6 7 8 9 ... 18 19 20 16 15 14 13 12 11.....1 => 20+14 = 34 : =========================================================================== : 18. 3 teaspoons = 1 tablespoons : 4 tablespoons = [?] cup : According to the information above, how many teaspoons are equal to [?] cup? : ans: E 一样想请问解题思路 同第一题 : =========================================================================== : 33.If x^4 + y^4 = 100, then the greast possible value of x is between : (A) 0 and 3 : (B) 3 and 6 : ans:B : 我原以为题目要x最大,所以就要y^4为0 : 也就是 直接求x^4=100 ,x的最小值为? : 但是答案不对,想请求正解! 设 y^4为0 求 x^4=100 (这样X才会是最大) 3^4 = 81 <100 (3.1)^4 = 92多 <100 所以介於 3-6 : ============================================================================ : 43.A committee of three people is to be chosen from four married couples. : What is the number of different committees that can be chosen if two people : who are married to each other cannot both serve on the committee? : (E)32 : ans:E : 我的解法是 : 4 2 : C * C = 8 四对couples中选出三对 * 两个人选一 : 3 1 : 似乎思路出了问题, 希望高手指正! C(4,3) 四对中选出三对 然後现在三对里面 两个人选一 C(2,1)*C(2,1)*C(2,1) (要做三次 因为有三组) =>4*8 = 32 以上 个人浅见 --

※ 发信站: 批踢踢实业坊(ptt.cc) ◆ From: 218.167.173.185 ※ 编辑: burgessx 来自: 218.167.173.185 (06/16 21:20)