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未解答：
15. 图出不来，手动描述，一个等边三角形的三个顶点都在圆上，三角形周长为24，求圆直径。
(A) 5(B) 8(C) 11(D) 15(E) 19
答案：C
我算出的半径是8/√3，√3=1.7，直径算出来是9.41啊，为什么答案是C？？
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1. A certain taxi company charges $3.10 for the first 1/5 of a mile plus $0.4 for each addtional 1/5 of a mile. What would this company charge for a taxi ride that was 8 miles long?【已解答D，谢谢pri344926443】 (A) $15.60 (B) $16.00 (C) $17.50 (D) $18.70 (E) $19.10 3.1+2*(8-0.2)
2. For every positive even integer n, the function h(n) is defined to be the product of all the even integers from 2 to n, inclusive. If p is the smallest prime factor of h(100) + 1, then p is【已解答E，谢谢pri344926443】
(A) between 2 and 10 (B) between 10 and 20
(C) between 20 and 30
(D) between 30 and 40
(E) greater than 40
*两个连续整数没有公因数，h（100）可算出因数是1-50的所有整数，因此h（100）+1的因数不包含1-50
3. When 2/3 of the garments in a shipment were inspected, 18 of the garments passed inspection and the remaining 2 garments failed. How many of the uninspected garments must pass inspection in order that 90 percent of the garments in the shipment pass? 【已解答B，谢谢pri344926443】
(A) 10
(B) 9
(C) 8
(D) 7
(E) 5
90%*[（18+2）*3/2]-18
4.(1+0.0001)/(0.04+10)
The value of the expression above is closest to which of the following? 【已解答C，谢谢Joyce_lzy】(A) 0.0001 (B) 0.001
(C) 0.1
(D) 1
(E) 10
不用管小数
5. The value of(10^9-10^4)/(10^8-10^5) is closest to which of the following?【已解答B，谢谢Joyce_lzy】
(A) 1 (B) 10
(C) 102
(D) 103
(E) 104
（10^5-1）/(10^4-10)
6. There are 10 children in a company's day-care center, and a pair of children is to be selected to play a game. At most, how many different pairs are possible?
【已解答D，谢谢pri344926443】
(A) 100 (B) 90
(C) 50
(D) 45
(E) 25
答案是45，C10里挑2个
为什么不能是从10个里先挑1个*9个里挑1个=90？先挑A后挑B和先挑B后挑A重复了，需要除2.
7.图片老是显示不出来：就是数轴上，以O点为圆心，在一二象限有个半圆，半圆上有P点（-√3，1），Q点（s，t），线段PO和QO形成一个直角，问Q的横坐标。
In the figure above, points P and Q lie on the circle with center O. What is the value of s ?【已解答B，谢谢pri344926443】
(A) 1/2
(B) 1
(C) √2
(D) √3
(E) √2/2
这道题完全没思路啊，求助，答案是B
8.Rates for having a manuscript typed at a certain typing service are $5 per page for the first time a page is typed and $3 per page each time a page is revised. If a certain manuscript has 100 pages, of which 40 were revised only once, 10 were revised twice, and the rest required no revisions, what was the total cost of having the manuscript typed? 【已解答 D】
(A) $430
(B) $620
(C) $650
(D) $680
(E) $770
这道题一不小心就掉进去了，答案是D，100*5+（40+10）*3+10*3
所有的page都type一遍，500刀；40pagerevise 第二次、10page也revise第二次，50*3刀；10page revise第三次，30刀
9.From a bag containing 12 identical blue balls, y identical yellow balls, and no other balls,one ball will be removed at random. If the probability is less than 2/5 that the removed ballwill be blue, what is the least number of yellow balls that must be in the bag? 【已解答C，谢谢xiangzhjs】
A. 17
B. 18
C. 19
D. 20
E. 21
概率问题，分母为总事件12+y，分子是从12个篮球中任选1个，因此是12/(12+y)<2/5，解出来y>18 ,最小是19
10. 50-59分的有2人，60-69分的有10人，70-79分的有16人，80-89分的有27人，90-99分的有18人。问which score interval contains the median of the 73 scores?
【已解答C，谢谢 荣耀和勇敢】
A. 60-69
B. 70-79
C. 80-89
D.90-99
E. can not be determined.
。。唉，题目问的是，这73个分数中，中位数在哪个区间。。。“73 scores”
11. If a certain sample of data has a mean of 20.0 and a standard deviation of 3.0, whichof the following values is more than 2.5 standard deviations from the mean? 【已解答A】
(A) 12.0
(B) 13.5
(C) 17.0
(D) 23.5
(E) 26.5
more than 2.5 standard deviation 的意思是原标准方差的2.5倍，所以是在上下7.5sd的区间内（12.5，27.5）。只有A不在这个区间内，是more than。
12.If m = 9/25, w = 15/32, and m + w + c = 1, which of the following gives the values ofm, w, and c in increasing order?【已解答A 谢谢 iriswine】
(A) c, m, w
(B) c, w, m
(C) m, w, c
(D) w, c, m
(E) w, m, c
把m，w大小算出来后，可以根据等式来排除选项。
13. The residents of Town X participated in a survey to determine the number of hours per week each resident spent watching television. The distribution of the results of the survey had a mean of 21 hours and a standard deviation of 6 hours. The number of hours that Pat, a resident of Town X, watched television last week was between 1 and 2 standard deviations below the mean. Which of the following could be the number of hours that Pat watched television last week?
【已解答D，谢谢lululuna】
(A) 30
(B) 20
(C) 18
(D) 12
(E) 6
在（21-6，（21-6）*2）的区间内，只有D符合。
14. For all positive integers m, 【m】 = 3m， when m is odd and m = 【1/2】 m ，when m is even. Which of the following is equivalent to 【9】 x 【6】 ?
【已解答D，谢谢lululuna】
(A) 【81】
(B) 【54】
(C) 【36】
(D) 【27】
(E) 【18】
题目出错：For all positive integers m, 【m】 = 3m， when m is odd and 【m】 = 1/2 m ，when m is even. Which of the following is equivalent to 【9】 x 【6】 ?
16. Last month 15 homes were sold in Town X.The average (arithmetic mean) sale price of the homes was $150,000 and the median sale price was $130,000.Which of the following statements must be true?【已解答A 谢谢 iriswine】
I.At least one of the homes was sold for more than $165,000.
II.At least one of the homes was sold for more than $130,000 and less than $150,000.
III.At least one of the homes was sold for less than $130,000.
A.I only
B.II only
C.III only
D.I and II
E.I and III
算总价，举反例核对
17. 187. If 0 < r < 1 < s < 2, which of the following must be less than 1 ? 【已解答A 谢谢 iriswine】
I. r/s
II. rs
III. s-r
(A) I only(B) II only(C) III only(D) I and II(E) I and II
这种题要拿两端来带入。
r=0.99, s=1.99 =>rs >1
18. If x>y^2>z^4, which of the following statements could be true? 【已解答E 谢谢 iriswine】
I. x>y>z
II. z>y>x
III. x>z>y
(A) I only
(B) I and II only
(C) I and III only
(D) II and III only
(E) I, II, and III
取test point的3个范围设定好，不会有重复。且x>0
19. If x is positive, which of the following could be the correct ordering of 1/x,2x,x^2？【已解答E 谢谢 iriswine】
I.x^2<2x<1/x
II. x^2<1/x<2x
III. 2x<x^2<1/x
(A) None
(B) I only
(C) III only
(D) I and II only
先把不等式换成等式，求出界限值。再取test point |
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