[外语类试卷]GRE（QUANTITATIVE）模拟试卷23及答案与解析.doc

1、GRE（ QUANTITATIVE）模拟试卷 23及答案与解析 0 Each of Questions 1 to 7 presents two quantities. Quantity A and Quantity B. Compare the two quantities. You may use additional information centered above the quantities if such information is given. Choose one of the following answer choices:A if Quantity A is grea

2、ter;B if Quantity B is greater;C if the two quantities are equal;D if you cannot determine the relationship based on the given information. 7 Each of Questions 1 to 7 presents two quantities. Quantity A and Quantity B. Compare the two quantities. You may use additional information centered above the

3、 quantities if such information is given. Choose one of the following answer choices:A if Quantity A is greater;B if Quantity B is greater;C if the two quantities are equal;D if you cannot determine the relationship based on the given information.15 In an office supply shop, pens that normally sell

4、for 89 cents each are on sale at 2 for $1.2How much can be saved by purchasing 12 of these pens at the sales price? （ A） $2.40 （ B） $2.94 （ C） $3.04 （ D） $4.80 （ E） $7.74 16 If the average(arithmetic mean)of 7 consecutive numbers is 16, what is the sum of the least and greatest of the 7 integers? （

5、A） 13 （ B） 14 （ C） 16 （ D） 19 （ E） 32 17 If 3x+4y=17 and 5x+2y=23, what is the value of x-y?_ 18 In the figure above, a small circle, with radius x, is inside a larger circle, with radius What is the area, in terms of x, of the shaded region? （ A） 6-2x （ B） 6-x2 （ C） 12-2x （ D） 36-2x （ E） 36-x2 19 I

6、f 4-3x least difference between elementary enrollment and secondary enrollment? （ A） 2000 （ B） 1995 （ C） 1990 （ D） 1985 （ E） 1980 35 The cost of books and materials accounted for approximately 30% of the school districts annual expenditures. In 1990, what was the approximate average cost per student

7、 for books and materials? （ A） $1,500 （ B） $2,000 （ C） $3,000 （ D） $6,000 （ E） It cannot be determined from the given information. 35 Mr. Hernandezs students filled out a survey asking how many hours each student watched television over 7 days. The results from the survey are shown below in a stem-a

8、nd-leaf plot. (Note: For example, 12 hours of television watched would have a stem value of 1 and a leaf value of 2) 36 Which of the following is the median number of hours of television watched during the week? （ A） 6 （ B） 12 （ C） 15.5 （ D） 16 （ E） 21 36 37 According to the graph, which of the foll

9、owing is the best estimate of the total revenue from government funding in 1990? （ A） $60 million （ B） $55 million （ C） $44 million （ D） $35 million （ E） $29 million 38 Each of the following is a valid conclusion that can be drawn from the information in the graph EXCEPT （ A） the total revenue from

10、tuition and government funding in 2000 was $120 million （ B） between 1980 and 1990, the proportion of total revenue from government funding increased （ C） revenue from government funding increased every year from 1950 to 2000 （ D） revenue from tuition increased every year from 1960 to 1990 （ E） reve

11、nue from tuition increased at a greater rate than revenue from government funding 38 39 Each of the following is a valid conclusion that can be drawn from the information in the graphs EXCEPT （ A） from 1970 to 1980, the number of stores increased by approximately 200 （ B） from 1970 to 2000, the numb

12、er of stores approximately doubled （ C） from 1980 to 2000, the average number of employees increased by approximately 50% （ D） in 2000, there were about 75,000 employees （ E） from 1970 to 2000, the number of employees increased each decade 40 Assume a 10% growth rate in the number of employees each

13、year from 2000 to 200Based on this information, which of the following represents the approximate total number of expected employees in 2002? （ A） 82,500 （ B） 85,000 （ C） 90,000 （ D） 90,750 （ E） 135,000 GRE（ QUANTITATIVE）模拟试卷 23答案与解析 1 【正确答案】 C 【试题解析】 The correct answer is C. Because the triangle in

14、 this problem is a right triangle, use the Pythagorean Theorem to compute the length of the hypotenuse, c, as follows: c2 = 62 + 82 c2 = 36 + 64 = 100 Thus c=10, and Quantity A and Quantity B are equal. If you recognized that the triangle is a 3-4-5 triangle you could have quickly arrived at the cor

15、rect answer. 2 【正确答案】 B 【试题解析】 The correct answer is B. To solve this problem, compute the averages of both lists of numbers. For Quantity A, the average of 11, 13, and 15 is , or 39/3, which equals 13. For Quantity B, the average of 12,14, and 16 is , or 42/3 which equals 14. Therefore, Quantity B

16、is greater than Quantity A. Another way to solve this problem is to note that all of the numbers in Quantity B are greater than those in Quantity A. Therefore, the average of Quantity B will be greater than the average of Quantity A. 3 【正确答案】 D 【试题解析】 The correct answer is D. To solve this problem,

17、try some test values for r, s, and t. Because it is given in the problem that they are negative numbers, r0, 5a is greater than a/5. However, when a 8 【正确答案】 A 【试题解析】 The correct answer is A. To solve this problem, find the interval of x for which(x+4)(x-2)0. For-42,(x+4)(x-2)0. Thus the interval of

18、 x for which(x+4)(x-2)-5 -3x-9x 20 【正确答案】 C 【试题解析】 The correct answer is C. To solve this problem, first square the value 0.0001:(0.0001)2 = 0.00000001 This value is equivalent to 110-8, because the decimal point is moved 8 places to the left. On the other hand, 0.001 is equivalent to 1 x 10-3, beca

19、use the decimal point is moved 3 places to the left. Thus, because = 105,0.001 is 105 times greater than(0.0001)2. 21 【正确答案】 E 【试题解析】 The correct answer is E. To solve this problem, first calculate the value of the third angle in the triangle. Because the angle is adjacent to a 105, its measure must

20、 be 75. Therefore, y must equal 180-75-35 = 70. 22 【正确答案】 72 【试题解析】 The correct answer is 72. Based on the given information, you know that the average is 13,500+450, or 30 hours. One standard deviation above the mean is 37 hours. The bell curve of a normal distribution puts the mean at 50%. One sta

21、ndard deviation in either direction is 34% away from the mean. So, one standard deviation is 84% of the employees. Since 84% of the employees work 37 hours, 16% work more than 37 hours. 16% of 450 employees = 72. 23 【正确答案】 D 【试题解析】 The correct answer is D, Because 48 square inches is times 32 square

22、 inches, Jaime should multiply the recipe ingredients by . 24 【正确答案】 B, C 【试题解析】 The correct answer is B and C. In this case, a multiple of x has to also be a multiple of 6. Therefore, both 12y and 30y are correct. 25 【正确答案】 D 【试题解析】 The correct answer is D. The first step in solving this problem is

23、 to set up an equation based on the net profit. Net profit is equivalent to revenue minus cost. In this problem, revenue is equal to 700x, and cost is equivalent to 6,000+300x. You are also given that net profit is 2400 and asked to calculate the number of microwaves, x. The equation is, therefore,

24、as follows: 700x-(6,000 + 300x)= 2,400 700x-6,000-300x=2,400 400x=8,400 x=21 26 【正确答案】 B 【试题解析】 The correct answer is B. In order to solve this problem, find the distance between the first number in the answer and 2.3, and see if that matches the distance between 2.3 and the second number. The only

25、pair for which this is true is -1.6 and 6.2; the distance between -1.6 and 2.3 is 3.9, and the distance between 2.3 and 6.2 is 3.9. 27 【正确答案】 700 【试题解析】 The correct answer is 700. To solve this problem, first calculate the width of the plot: P = 2w+2l 110 = 2w+2(35) 110-70 = 2w 40 = 2w 20 = w The ar

26、ea is 1w= 3520 = 700. 28 【正确答案】 A 【试题解析】 The correct answer is A. First, set up equations to represent the given averages: Next, simplify the first equation: c+d=24Now, substitute this value into the second equation and solve for e: 24 + e = 30 e = 6 29 【正确答案】 A 【试题解析】 The correct answer is A. To so

27、lve this problem, first set it up:(x-y)-z-(x-(y-z). Now simply perform the subtraction(pay attention to the negative signs!)to get -2z. 30 【正确答案】 99 【试题解析】 The correct answer is -9. The goal would be to make x+y or y-x as big as possible. The biggest x+y is 9(5+4). Then y-x is-1(4-5). -1x9=-9. 31 【正

28、确答案】 D 【试题解析】 The correct answer is D. If the area of the square is 50, then one side of the square is or . The diagonal of an inscribed square is equal to the diameter of the circle. The diagonal creates 2 isosceles right triangles. Use the Pythagorean Theorem: . Simplify the equation and you get c

29、=10. If the diameter is 10, then the radius is 5. Since the area of a circle is r2, the area of this circle is 25. 32 【正确答案】 D 【试题解析】 The correct answer is D. To solve this problem, simply calculate 24% of 1,650; 1650(0.24)= 396. You could also estimate to arrive at an answer: 1,650 is about 1,600 a

30、nd 24% is approximately 25%. Therefore, 24% of 1,650 is close to 25% of 1,600, which is 400. 33 【正确答案】 B 【试题解析】 The correct answer is B. Because 6% of the graduating class is currently student teaching and 42% of the graduating class is currently seeking immediate employment, the ratio of graduates

31、who are student teaching to graduates who are seeking immediate employment is 6:42, which reduces to 1:7. 34 【正确答案】 E 【试题解析】 The correct answer is E. According to the graph, in 1980, the difference between elementary enrollment and secondary enrollment was approximately 1,000 - 500, or 500 students.

32、 In every other year, the difference in enrollment was at least twice that number. 35 【正确答案】 B 【试题解析】 The correct answer is B. According to the graph, district expenditures in 1990 were $20 million. Therefore, the school district spent about $6 million on books and materials. The graph shows that th

33、ere were 3,000 students enrolled in 1990, so the district spent $2,000 per student on books and materials. 36 【正确答案】 D 【试题解析】 The correct answer is D. The median is the middle value in an ordered set of values. Based on the information given, the median of the set of values is 16. 37 【正确答案】 C 【试题解析】

34、 The correct answer is C. According to the graph, the bar that represents the revenue from government funding in 1990 is slightly below the line representing $45 million. Thus, $44 million is the logical answer choice. 38 【正确答案】 B 【试题解析】 The correct answer is B. According to the graph, it is apparen

35、t that revenue from government funding increased between 1980 and 1990. However, in 1980, revenue from government funding was greater than revenue from tuition, but in 1990 revenue from government funding was less than revenue from tuition. Thus, between 1980 and 1990, the proportion of total revenu

36、e that came from government funding decreased. 39 【正确答案】 E 【试题解析】 The correct answer is E. According to the graph, the slope of the line segment between the number of employees in 1970 and the number of. employees in 1980 is negative(slopes down). Thus, the number of employees decreased between 1970

37、 and 1980; the statement “From 1970 to 2000, the number of employees increased each decade“ is therefore false. 40 【正确答案】 D 【试题解析】 The correct answer is D. You are given that the rate of increase is 10%. According to the graph, there were approximately 75,000 employees in 2000. Therefore, you should expect 75,000 + 7,500 = 82,500 employees in 2001. You should expect 82,500 + 8,250 = 90,750 employees in 2002.