OG中的新GRE数学题解析(7)
GRE_OG_数学精选
1.y=2x2+7x – 3x y本体答案不确定。
我开始做的时候被题目放了烟雾弹，以为要经过什么特别处理，像配方啥的。
但配着配着就感觉不对劲，x与y只有函数关系，没有绝对的大小关系嘛。
汗2.The figure above shows the graph of a function f, defined by f(x)=|2x|+4for all numbers x. For which of the following functions g defined for allnumbers x does the graph of g intersect the graph of f ?A g(x)=x–2B g(x)=x+3C g(x)=2x – 2D g(x)=2x+3E g(x)=3x – 2这个题就是问两个函数图象相交的问题，根据观察，要与这个折线相交的直线的斜率满足的条件是要么是正斜率比2大，要么是负斜率比-2小，因此只能选E了。
3.Each employee of a certain company is in either Department X orDepartment Y, and there are more than twice as many employees inDepartment X as in Department Y. The average (arithmetic mean) salaryis $25,000 for the employees in Department X and is $35,000 for theemployees in Department Y. Which of the following amounts could bethe average salary for all of the employees in the company?Indicate all such amounts.A $26,000B $28,000C $29,000D $30,000E $31,000F $32,000G $34,000本题我们要注意到题目中的more than twice的字眼，我们当做twice算的时候，结果是（25000*2+35000）/3约等于28333，因为有more than，所以选的答案要么是比前面这个数大，要么小，又由于more的是X部门的，那么肯定会将平均工资给拉低了，因此，选比前面那个数小的答案，AB都可以了。
GRE数学考试真题与解析
G R E数学考试真题与解析-CAL-FENGHAI-(2020YEAR-YICAI)_JINGBIANGRE数学考试真题与解析GRE数学考试真题与解析的内容小编在下文介绍了一部分，更多GRE数学真题小编还会为大家继续分享，敬请关注。
1. 从1,2,3,4,5,6,7,8,9中选出三个数字组成一个三位数,这个三位数的digits中有两个相同,另一个digit与其它两个都不同,问共有多少个这样的三位数?(A) 72(B) 144(C) 180(D) 216(E) 542. 符合 X^2+Y^2<=100的整数解共有多少对?3. A box contains 100 balls, numbered from 1 to 100. If three balls are selected at random and with replacement from the box,what is the probability that the sum of the three numbers on the balls selected from the box will be odd?(A) 1/4(B) 3/8(C) 1/2(D) 5/8(E) 3/44. Right triangle PQR is to be constructed in the xy-plane so that the right angle is at P and PR is parrallel to the x-axis. The x-and y-coordinates of P,Q,and Rare to be integers that satisfy the inequalities -4<=x<=5,6<=y<=16,how many different triangles with these properties could be constructed?(A) 110(B) 1100(C) 9900(D) 10000(E) 121005. (0-9) 要组成三位电话号码,第一位不能是0或1,三位数中相邻两位不能为同一数. (e.g. 227 not acceptable, but 272 acceptable),求可以组成多少个这样的电话号码?参考答案：1.解：因为三个数中两个数相同，所以从9个数中取出两个的可能性为，三个数中那个不同的数和可能位置为3个，取出的两个数哪个做不同的数的可能性为两种2.解：本题的意为一个半径为10的圆中的整数对有多少对。
gmat数学试题及答案
gmat数学试题及答案GMAT数学试题及答案1. 题目：如果一个数列的前三项分别是2，4，8，那么这个数列的第四项是多少？答案：这个数列的第四项是16。
2. 题目：一个长方形的长是宽的两倍，如果宽增加10%，长减少10%，那么新的长方形面积比原来增加了多少百分比？答案：新的长方形面积比原来减少了1%。
3. 题目：一个工厂生产了1000个零件，其中90%是合格的。
如果不合格的零件中有20%被重新加工并合格，那么工厂最终有多少个合格的零件？答案：工厂最终有918个合格的零件。
4. 题目：如果一个圆的半径增加10%，那么它的面积增加了多少百分比？答案：它的面积增加了21%。
5. 题目：一个投资组合由两种股票组成，股票A占60%，股票B占40%。
如果股票A的回报率是10%，股票B的回报率是15%，那么整个投资组合的平均回报率是多少？答案：整个投资组合的平均回报率是12%。
6. 题目：一个班级有50名学生，其中30%是女生。
如果班级中女生的平均成绩是80分，男生的平均成绩是70分，那么整个班级的平均成绩是多少？答案：整个班级的平均成绩是75分。
7. 题目：一个商店销售两种类型的电视机，A型和B型。
如果A型电视机占总销售量的40%，并且A型电视机的利润率是20%，B型电视机的利润率是30%，那么商店从A型电视机中获得的总利润占总利润的百分比是多少？答案：商店从A型电视机中获得的总利润占总利润的44%。
8. 题目：如果一个数的平方根是4，那么这个数的立方根是多少？答案：这个数的立方根是8。
结束语：以上就是GMAT数学试题及答案，希望能够帮助考生们更好地准备考试。
2019年新GRE数学11道练习题及答案解析
2019年新GRE数学11道练习题及答案解析1：还有数列题：a1=2，a2=6，an=an-1/an-2，求a150.解答： an=an-1/an-2,所以an-1=an-2/an-3,带入前式得an=1/an-3,然后再拆一遍得到an=an-6,也就是说,这个数列是以6为周期的,则a150=a144=...=a6,利用a1,a2能够计算出a6=1/3.如果实在想不到这个方法,能够写几项看看很快就会发现a150=a144,大胆推测该数列是以6为周期得,然后写出a1-a13(也就是写到你能看出来规律),不难发现a6=a12,a7=a13,然后那,稍微数数,就能够知道a150=a6了,同样计算得1/3.2：问摄氏升高30度华氏升高的度数与62比大小.key：F=30*9/5=54Myanswer：加起来=695：24，36，90，100四个数中,该数除以它的所有的质因子，最后的结果是质数的是那个：Key：906：0.123456789101112….，这个小数无限不循环地把所有整数都列出来.请问小数点后第100位的数字是多少?Key：位数0 1 2 3 4 5 6 7 8 9 1010 11 12 ………………………19 2020 21……………………………29 2030……………………………… 39 2040……………………………… 49 2050 51 52 53 54 55 56 ――――――第101位 =5??7：2904x=y2(y的平方)，x、y都是正整数，求x的最小值。
因为：X^2×Y^2×Z^2=(X×Y×Z)^2所以把2904除呀除=2×2×2×3×11×11=2^2×11^2×6再乘一个6就OK了2^2×11^2×6×6=(2×11×6)^2=132^2Key：最小的x=68：序列An=1/n-1/(n+1),n>=1,问前100项和.解答：An =1/n-1/(n+1)An-1=1/(n-1)-1/nAn-2=1/(n-2)-/(n-1)A1=1-1/2把左边加起来就是An+An-1+……+A1=1-1/(n+1) ...消掉了好多好多项之后的结果Key：把n=100带入得前100项之和为100/1019：等腰三角形，腰为6.底边上的高为x,底边为y,问4x2+y2和144谁大解答：勾股定理得(y/2)2+x2=62,所以4x2+y2=14410：-1Key：我想的办法只能是尝试：原式=r(1+t*t)恒小于零1)r -1， t 0 则原式 -12)r -1， t -1则原式 -23)r 0 ， t 0 则原式 0例如：r=-0.9 t=-1/3 时,原式=-1,若此时-0.9-1.11：有长方形4feet*8feet,长宽各截去x inch,长宽比2：5，解答：列出方程4*12-x)/(8*12-x)=2/5 => x=16。
2024 GRE考试专题数学历年真题集锦
2024 GRE考试专题数学历年真题集锦GRE考试是对申请美国研究生院的学生进行综合能力测试的重要方式之一。
其中，数学部分是考生必须重点准备和应对的内容之一。
为了帮助考生更好地备考，本文整理了2024年GRE考试数学部分的历年真题集锦，供考生参考和复习使用。
一、整数和1. 如果a和b都是正整数，且a + b = 8，那么a和b可能的取值有哪些？答案：(1, 7), (2, 6), (3, 5), (4, 4)2. 如果m和n都是正整数，且m - n = 14，那么m和n的最小公倍数是多少？答案：28二、几何1. 一根长为10英尺的绳子被剪成两段，使得其中一段的长度是另外一段的2倍。
求较短一段的长度。
答案：4英尺2. 一个半径为5的圆与一个半径为8的圆相切于一点，并且两个圆的圆心之间的距离为13。
求两个圆相切点之间的距离。
答案：12三、代数1. 如果a是一个正整数，并且a^2 - 5a + 6 = 0，那么a的值是多少？答案：2或32. 设a、b、c是正整数，且满足a + b = c。
若a能被5整除，c能被9整除，那么b能被几整除？答案：4四、概率与统计1. 在一个有10个数字的集合中，每一个数字都是从1到10中随机选取的，那么从这个集合中选取一个数字，并且这个数字是偶数的概率是多少？答案：1/22. 一张标准扑克牌中红桃的数量为13，黑桃的数量为13。
从扑克牌中随机抽取一张牌，那么这张牌为红桃或黑桃的概率是多少？答案：26/52 = 1/2通过以上历年真题的集锦，考生可以更好地理解GRE数学部分的题目类型和解题思路。
每个题目的解答都提供了详细的答案，考生可以通过演算来验证答案的正确性，并进行自我评估。
为了顺利完成GRE考试，考生需要做到以下几点：首先，掌握基础知识。
GRE数学部分主要考察考生对数学基本概念和方法的理解和运用能力。
因此，考生需要熟悉数学基本概念和公式，同时要能够快速准确地运用这些概念和公式解题。
新GRE真题和OG填空详解
(OG Text Completion Sample Questions 2) Vain and prone to violence, Caravaggio could not handle success: the more his (i) ______ as an artist increased, the more (ii) ______ his life became.BLANK (i) (A) temperance (B) notoriety (C) eminenceKEY: CD 1. 2. 3. 4. 5. [1]. [2]. [3]. [4]. [5]. [6].BLANK (ii) (D) tumultuous (E) providential (F) dispassionate关键字：冒号确定 blank1 中应该填入一个名词，表示 C 作为一名艺术家在某一方面的成绩， blank2 中应该填入一个形容词，表示 C 的生活的变化形式；发现句子中有冒号，可以推断句子前后两部分是一种解释说明的关系，即句子前后两部分意思一致，前半句说 C 对于成功的把握很差，而且倾向于暴力；则后半句也应该是同样的意思；在后半句中，as an artist increased 应该对应的是―成功‖的意思，从 blank1 中选出―eminence‖，而 his life became，对应的是其倾向于暴力的部分，从blank2 中选出―tumultuous‖。
词语解释： (A) temperance：（抑制、温和）moderation in action, thought, or feeling : RESTRAINT (B) notoriety：（臭名昭著）the quality or state of being widely and unfavorably known (C) eminence：（声名显赫）one that is eminent, prominent, or lofty (D) tumultuous：（暴力的）marked by violent or overwhelming turbulence or upheaval (E) providential：（神意的）of, relating to,or determined by God conceived as the power sustaining and (F) dispassionate：（冷静的）not influenced by strong feelingguiding human destiny(OG Text Completion Sample Questions 3) In parts of the Arctic, the land grades into the landfast ice so ______ that you can walk off the coast and not know you are over the hidden sea. (A) (B) (C) (D) (E) permanently imperceptibly irregularly precariously relentlesslyKEY: B 1. 2. 关键字：“So … that …”结构―So … that …‖结构，that 后面的部分对于 so 后面的词进行解释说明，其表示的是 arcitic 附近的某些冰层向海中伸出的程度，如果仅仅说是能够让人行走的话，选项中没有合适的词语进行对应，因而，形容的是给人们的一种感觉，对应部分如颜色标注。
解题干货重拳出击丨GRE数学易错题型全解析
解题干货重拳出击丨GRE数学易错题型全解析GRE数学总是容易被忽略，一不小心就会在这些题上面丢分，看看这些易错题，是不是你踩过的坑。
01被除数计算问题余数考点中被除数计算的题型，一般是在题目当中给出除数和余数，问满足要求的被除数。
这类题型计算的方法是利用公式：被除数＝除数×商＋余数。
需要注意的是各个数的取值范围：被除数和除数都是正整数；商是非负整数；0≤余数≤除数。
【例】How many positive integers less than 100 have a remainder of 2 when divided by 13?A. 6B. 7C. 8D. 9E. 10答案C.【易错点】商只算了正整数，没有把0算进去。
【解析】问小于100的正整数当中，满足除以13余2的数有多少个？可以假设除以13余2的数是：x＝13n＋2，其中n是非负整数.那么根据题意可以列不等式：0＜13n＋2＜100.解得-2/13＜n＜98/13，因为n是非负整数，所以n可以取0到7这几个整数，一共8个取值，对应的x就有8个取值.02概率计算问题事件之间的关系常见的有三种：互斥、对立、独立。
简单来区别一下：互斥事件是指两个事件不能同时发生；对立事件是指两个事件的发生非此即彼；独立事件是指事件之间互不影响。
在分析题目当中的事件时，首先要理解的就是事件之间的关系。
【例】For a certain probability experiment, the probability that event A will occur is 1/2 and the probability that event B will occur is 1/3.Which of the following values could be the probability that the event A ∪ B (that is, the event A or B, or both) will occur?Indicate all such values.A.1/3B.1/2C.3/4答案BC.【易错点】题干没有告知两个事件的关系，默认为是独立事件。
新GRE数学考试算术题试题及答案
新GRE数学考试算术题试题及答案新GRE数学考试算术题精选试题及答案1．A,B,C,D,E五个人的薪水的median是20000,range不超过50000,其中A,B,C的薪水分别是20000, 40000, 50000,问五个人薪水的平均值可能是多少?(A) 20000(B) 32000(C) 18000(D) 23000(E) 310002. 一个样本在一个标准方差内的概率是0.68,两个标准方差内的概率是0.95. 一样本,mean=18.6,标准方差是6,求:该样本在6.6-12.6内占多少?(A) 0(B) 0.68(C) 0.27(D) 0.36(E) 0.1353. 一组数平均值9,标准方差2,另外一组数平均值3,标准方差1,问第一组数在(5,11)中的数占总数的比例和第二组数在(1,4)中的数占总数的比例哪个大?4. 有100个人都对A,B两个人进行评价,每个人只有两种选择,即好或不好,说A不好的.有59个,说B不好的有65个,问:同时说AB都好的人数和35比较,哪个大?5. 两个集合: A=[-1,-2,-3,-4] B=[-2,3,4,5],问B的A次方有多大的概率是正数?(A) 0(B) 0.5(C) 0.625(D) 0.875(E) 0.135参考答案：1.解：median为20000，range为50000，则本题剩下两数的最小值为0，0，最大值为20000，2000，则平均值最小值为：(0+0+20000+40000+50000)/5 =22000。
平均最大值为：(20000+20000+20000+40000+50000)/5=30000。
所以五人薪水平均值应在 22000和30000之间。
2.解：本题应加入限制条件：应在正态分布中，否则无解。
Weight指平均值，6.6-12.6 指-2个方差与-1个方差之间的概率，所以算发为：(0.95-0.68)/2=0.1353.解：本题同上题，需在正态分布中讨论，(5，11)中的数是1.5个方差中的数，同样(1，4)中的数也是1.5个方差中的数，所以两组数占总数的比例一样大。
最新GRE数学样题解析
最新：新gre数学样题及解析GRE® Revised General Test: Quantitative Reasoning Sample QuestionsFiguresThis document includes figures, which appear on screen. Following each figure on screen is text describing that figure. Readers using visual presentations of the figures may choose to skip parts of the text describing the figure that begin with “Begin skippable figure description” and end with “End skippable figure description.”Mathematical Equations and ExpressionsThis document includes mathematical equations and expressions. Some of the mathematical equations and expressions are presented as graphics. In cases where a mathematical equation or expression is presented as a graphic, a verbal presentation is also given and the verbal presentation comes directly after the graphic presentation. The verbal presentation is in green font to assist readers in telling the two presentation-modes apart. Readers using audio alone can safely ignore the graphical presentations, and readers using visual presentations may ignore the verbal presentations.IntroductionThe revised Quantitative Reasoning section contains four types of questions:Multiple-choice Questions — Select One Answer ChoiceMultiple-choice Questions — Select One or More Answer ChoicesNumeric Entry QuestionsQuantitative Comparison QuestionsEach question appears either independently as a discrete question or as part of a set of questions called a Data Interpretation set. All of the questions in a Data Interpretation set are based on the same data presented in tables, graphs, or other displays of data. Below are descriptions, directions, and samples of each type of question.Multiple-Choice Questions — Select One Answer ChoiceThese questions are multiple-choice questions that ask you to select only one answer choice from a list of five choices.Sample QuestionsDirections: Select a single answer choice.Sample question 1 below is based on figure 1.Figure 1Begin skippable figure description.Figure 1 is a circle with center C.Two diameters of the circle are drawn, dividing the circle into 4 sectors. Two nonadjacent sectors are shaded, and the central angle of one of the unshaded sectors measures 160 degrees.End skippable figure description.1. Figure 1 above shows a circle with center C and radius 6. What is the sum of the areas of the two shaded regions?A. 7.5 piB. 6 piC. 4.5 piD. 4 piE. 3 piAnswer: D ( 4 pi)Sample question 2 below is based on figure 2.Figure 2Begin skippable figure description.Figure 2 shows the graph in the x y plane of the function f of x = the absolute value of 2x, end absolute value, + 4. There are equally spaced tick marks along the x axis and along the y axis. The first tick mark to the right of the origin, and the first tick mark above the origin, are both labeled 1.The graph of the function f is in the shape of the letter V. It is above the x axis and is symmetric with respect to the y axis.The lowest point on the graph of f is the point 0 comma 4 on the y axis.Going leftward from the point 0 comma 4 the graph of fis a line that slants upward, passing through the point negative 2 comma 8.Going rightward from the point 0 comma 4 the graph of f is a line that slants upward, passing through the point 2 comma 8.End skippable figure description.2. Figure 2 above shows the graph of a function f, defined by f of x = the absolute value of 2x, end absolute value, + 4 for all numbers x. For which of the following functions g defined for all numbers x does the graph of g intersect the graph of f?A. g of x = x minus 2B. g of x = x + 3C. g of x = 2x minus 2D. g of x = 2x + 3E. g of x = 3x minus 2Answer: E (g of x = 3x minus 2)Multiple-Choice Questions — Select One or More Answer ChoicesThese questions are multiple-choice questions that ask you to select one or more answer choices from a list of choices. A question may or may not specify the number of choices to select.Sample QuestionsDirections: Select one or more answer choices according to the specific question directions.If the question does not specify how many answer choices to select, select all that apply.The correct answer may be just one of the choices or may be as many as all of the choices, depending on the question.No credit is given unless you select all of the correct choices and no others.If the question specifies how many answer choices to select, select exactly that number of choices.1. Each employee of a certain company is in either Department X or Department Y, and there are more than twice as many employees in Department X as in Department Y. The average (arithmetic mean) salary is $25,000 for the employees in Department X and is $35,000 for the employees in Department Y. Which of the following amounts could be the average salary for all of the employees in the company?Indicate all such amounts.A.$26,000B. $28,000C. $29,000D. $30,000E. $31,000F. $32,000G. $34,000Answer: A ($26,000) and B ($28,000)2. If f, g, and h are positive integers, f is a factor of g, and g is a factor of h, which of the following statements must be true?Indicate all such statements.A. f is a factor of g squared.B. f is a factor of gh.C. f is a factor of h minus g.Answer: A (f is a factor of g squared), B (f is a factor of gh.), and C (f is a factor ofh minus g)Numeric Entry QuestionsQuestions of this type ask you either to enter the answer as an integer or a decimal in a single answer box or to enter it as a fraction in two separate boxes — one for the numerator and one for the denominator. In the computer-administered test, the computer mouse and keyboard are used to enter the answer.Sample QuestionsDirections: Enter your answer in the answer box(es) below the question.Equivalent forms of the correct answer, such as 2.5 and 2.50, are all correct. Fractions do not need to be reduced to lowest terms.Enter the exact answer unless the question asks you to round your answer.1. If x= 10 to the power negative 1, what is the value ofopen parenthesis, x+ the fraction 1 over x, close parenthesis, times, open parenthesis, 1 over x, close parenthesis?Answer BoxAnswer: 1012. A university admitted 100 students who transferred from other institutions. Of these students, 34 transferred from two-year community colleges, 25 transferred from private four-year institutions, and the rest transferred from public four-year institutions. If two different students are to be selected at random from the 100 students, what is the probability that both students selected will be students who transferred from two-year community colleges?Give your answer as a fraction.Fraction answer boxesAnswer: 17 over 150 (or any equivalent fraction).Quantitative Comparison QuestionsQuestions of this type ask the examinee to compare two quantities — Quantity A and Quantity B — and then determine which of four statements describes the comparison.Sample QuestionsDirections: Compare Quantity A and Quantity B, using the additional information given, if any. Select one of the following four answer choices.A. Quantity A is greater.B. Quantity B is greater.C. The two quantities are equal.D. The relationship cannot be determined from the information given.A symbol that appears more than once in a question has the same meaning throughout the question.1.Quantity A: x squared + 1Quantity B: 2x, minus 1A. Quantity A is greater.B. Quantity B is greater.C. The two quantities are equal.D. The relationship cannot be determined from the information given.Answer: A (Quantity A is greater.)Sample question 2 below is based on figure 3.Figure 3Begin skippable figure description.Figure 3 shows parallelogram RSTU. Sides R U and S T are horizontal, with S T above, and slightly to the left of side R U. Diagonal S U, which extends from vertex S at the upper left of theparallelogram to vertex U at the lower right of the parallelogram, divides the parallelogram into two triangles, R S U and U S T; and the angle at vertex S into 2 adjacent angles R S U and U S T. The measure of angle R S U is x degrees, and the measure of angle U S T is y degrees.End skippable figure description.2.It is given that RSTU is a parallelogram.Quantity A: xQuantity B: yA. Quantity A is greater.B. Quantity B is greater.C. The two quantities are equal.D. The relationship cannot be determined from the information given.Answer: D (The relationship cannot be determined from the information given.) Data Interpretation SetsData Interpretation questions are grouped together and refer to the same table, graph, or other data presentation. These questions ask you to interpret or analyze the given data. The types of questions may be Multiple-choice (both types) or Numeric Entry.Sample QuestionsDirections: Questions 1 to 3 are based on the data in the following table.The table shows the percent change in monthly value of inventory at six businesses from+8minus 5+12minus 5minus 10Note: Inventory values are determined at the end of each month.1. If the value of inventory at Business K was $30,000 for April, what was the value of inventory at Business K for June?A. $22,500B. $29,925C. $30,000D. $33,000E. $33,075Answer: B ($29,925)2. At Business M, the value of inventory for May was what percent of the value of inventory for June?Give your answer to the nearest 0.1 percent.% Answer box followed by percent signAnswer: 89.33. For which of the six businesses shown was the percent change in value of inventory from April to June greatest?A. GB. KC. MD. RE. VAnswer: A (Business G)Directions: Questions 4 to 6 are based on the data shown in figure 4.Figure 4Begin skippable figure description.The title of the data in figure 4 is “Workforce of Country X.”The data consists of a pie chart and a bar graph. The title of the pie chart is “Percent Distribution of Workforce by Employment Sector” and the title of the bar graph is “Workforce in the Service Sector by Area and Gender.”The percent distribution of the workforce by employment sector in the pie chart is as follows: Professional Sector 20%.Service Sector 15%Construction and Maintenance Sector 10%Production and Transportation Sector 15%Other Sector 15%Sales Sector 10%Management Sector 15%The bar graph shows the number of males and females in each of the five service sectors. The bar graph has horizontal bars. The graph has a horizontal axis labeled Millions of People, with vertical gridlines in multiples of 0.5 million, from 0.5 million to 4 million. Five Service Sector areas are listed along the vertical axis. The data in the bar graph is as follows:Health Care Sector, 0.5 million males and 2.75 femalesProtective Service Sector, a little under 2 million males and 0.5 million femalesFood Service Sector, a little under 3 million males and a little under 4 million femalesPersonal Care Sector, a little over 0.5 million males and about 2.75 million femalesOther Sector, a little under 3 milllion males and a little under 2 million femalesEnd skippable figure description.4. Approximately how many people are in the production and transportation sector of the workforce?A. 9 millionB.12 millionC. 15 millionD. 18 millionE. 21 millionAnswer: E (21 million)5. In the workforce, the ratio of the number of males to the number of females is the same for the sales sector as it is for the protective service area of the service sector. Which of the following is closest to the number of females in the sales sector?A. 2.9 millionB. 3.6 millionC. 10.4 millionD. 11.1 millionE. 14.0 millionAnswer: A (2.9 million)。
GRE考试OG逻辑题目解析
GRE考试OG逻辑题目解析GRE考试OG逻辑题目解析1,Parland’s alligator population has been declining in recent years，primarily because of hunting. Alligators prey heavily on a species of freshwater fish that is highly valued as food by Parilanders，who had hoped that the decline in the alligator population would lead to an increase in the numbers of these fish available for human consumption. Yet the population of this fish has also declined，even though the annual number caught for human consumption has not increased.P地区的短吻鳄数量近些年下降，主要原因是捕猎。
短吻鳄捕食的淡水鱼是P居民的食物，P居民希望短吻鳄数量的下降能够导致这种可供人们消费的鱼的数量上升。
但是这种鱼的数量也下降了，即使它每年被人类抓住消费的的量没有增加。
Which of following，if true，most help to explain the decline in the population of the fish species?下列哪个选项如果是对的，最有效地解释了鱼的数量下降?A.The decline in the alligator population has meant that fishers can work in some parts of lakes and rivers that were formerly too dangerous.短吻鳄数量的下降意味着渔民能够到以前湖里和江河里那些以前很危险的地方工作。
GRE_OG_数学精选
1.y=2x2+7x – 3x y本体答案不确定。
我开始做的时候被题目放了烟雾弹，以为要经过什么特别处理，像配方啥的。
但配着配着就感觉不对劲，x与y只有函数关系，没有绝对的大小关系嘛。
汗2.The figure above shows the graph of a function f, defined by f(x)=|2x|+4for all numbers x. For which of the following functions g defined for allnumbers x does the graph of g intersect the graph of f ?A g(x)=x–2B g(x)=x+3C g(x)=2x – 2D g(x)=2x+3E g(x)=3x – 2这个题就是问两个函数图象相交的问题，根据观察，要与这个折线相交的直线的斜率满足的条件是要么是正斜率比2大，要么是负斜率比-2小，因此只能选E了。
3.Each employee of a certain company is in either Department X orDepartment Y, and there are more than twice as many employees inDepartment X as in Department Y. The average (arithmetic mean) salaryis $25,000 for the employees in Department X and is $35,000 for theemployees in Department Y. Which of the following amounts could bethe average salary for all of the employees in the company?Indicate all such amounts.A $26,000B $28,000C $29,000D $30,000E $31,000F $32,000G $34,000本题我们要注意到题目中的more than twice的字眼，我们当做twice算的时候，结果是（25000*2+35000）/3约等于28333，因为有more than，所以选的答案要么是比前面这个数大，要么小，又由于more的是X部门的，那么肯定会将平均工资给拉低了，因此，选比前面那个数小的答案，AB都可以了。
教gre数学题
教gre数学题1.最经典的gre数学题最经典的gre数学题，gre数学10道经典题练习的题目是：一个数字（一共有4篇）；一个数字（两个数字）；另一个数字（两个数字）；两个数字（两个数字）。
数字推理的题目有两种类型：1.数字推理。
2.数字推理。
这三种类型题目都是同一套题目里面的。
这三种类型题目里面可以同一套题目里面的数字推理。
这两种类型的题目有一个共同点，叫做“推理”，即“推理”，“推理”。
这种题目的答案在我们的gre数学里可以称为“推理”或“推理”。
但是这两种题目的答案往往是“推理”这两个词。
这两种题型有两个类型：1.推理。
2.推理。
这类题目的答案基本上都可以归纳出来了，比如：①正确的推理2.gre数学经典难题最经典的gre数学题，gre数学10道经典题练习一共35道题，平日做完13套题，平日刷完15套左右。
最后一题是16分。
这个题目做的不错，但也很正常。
我是16年高考，数学考了120分，考前一个月，做完14套题，一共12套题。
这个题目做起来，做完之后再回头看题做，这个时候很难做。
我不知道怎么做的，就说做题，做精听。
做完之后再看答案，把不懂的单词记下来。
这种做题技巧，不管是做题还是做精听，都会有用。
我考完gre后，做完精读的时候，我发现我的做题方式和精听是有一定区别的，但是精听完了再精听之后就忘了。
我做精听时，就感觉，没听懂的就是做精听。
精听完完之后，再去看文本，一边听一边写精听，边关键词，把没听到的关键词查看。
3.最经典的gre数学题最经典的gre数学题，gre数学10道经典题练习一个月，最后考试结束之前一共考了四次，分别是verbal164，w4.5，verbal165，quant175，w4。
这三个月里，我的方法是，刷题+总结，刷题+总结。
第一次考gre，刷过一次数学，总分333（刷过一次），verbal164，w4,r30，w5.6，w5.0。
这两个月里，我总共刷了一次数学，没错，刷了几套题，刷题+总结。
2019年新GRE数学11道练习题及答案解析
2019 年新GRE 数学11 道练习题及答案解析1 ：还有数列题：a1=2，a2=6，an=an-1/an-2 ，求a150.解答：an=an-1/an-2, 所以an-1=an-2/an-3, 带入前式得an=1/an-3, 然后再拆一遍得到an=an-6, 也就是说, 这个数列是以 6 为周期的,则a150=a144=...=a6,利用a1,a2能够计算出a6=1/3.如果实在想不到这个方法, 能够写几项看看很快就会发现a150=a144,大胆推测该数列是以6为周期得，然后写出a1-a13（也就是写到你能看出来规律）,不难发现a6=a12,a7=a13,然后那，稍微数数，就能够知道a150=a6 了,同样计算得1/3.2：问摄氏升高30度华氏升高的度数与62比大小.key: F=30*9/5=54Myanswer：加起来=695：24，36，90，100四个数中, 该数除以它的所有的质因子，最后的结果是质数的是那个：Key：906: 0.123456789101112….，这个小数无限不循环地把所有整数都列出来.请问小数点后第100位的数字是多少?Key：位数0 1 2 3 4 5 6 7 8 9 1010 11 12 ……………………… 19 2020 21 ....................................... 29 2030 ............................................. 39 2040 ............................................. 49 2050 51 52 53 54 55 56 第101 位=5??7：2904x=y2(y 的平方) ，x、y 都是正整数，求x 的最小值。
因为：X A2X Y A2X Z A2=(X X Y X Z)A2所以把2904 除呀除=2X2X2X3X 11X 11=2八2乂1M2X6 再乘一个6就OK了2A2X11A2X6X6=(2X11X6)A2=132A2Key:最小的x=68：序列An=1/n-1/(n+1),n>=1, 问前100项和.解答：An =1/n-1/(n+1)An-1=1/(n-1)-1/nAn-2=1/(n-2)-/(n-1)A1=1-1/2把左边加起来就是An+An-1+……+A仁1-1/(n+1) ... 消掉了好多好多项之后的结果Key:把n=100带入得前100 项之和为100/1019:等腰三角形，腰为6.底边上的高为x,底边为y,问4x2+y2和144 谁大解答:勾股定理得(y/2)2+x2=62, 所以4x2+y2=14410: -1Key:我想的办法只能是尝试：原式=r(1+t*t) 恒小于零1) r -1 ，t 0 则原式-12) r -1 ，t -1 则原式-23) r 0 ，t 0 则原式0 例如：r=-0.9 t=-1/3 时,原式=-1, 若此时-0.9-1. 11：有长方形4feet*8feet, 长宽各截去x inch, 长宽比2：5，解答：列出方程4*12-x)/(8*12-x)=2/5 => x=16。
新GRE数学样题解析
最新：新g r e数学样题及解析GRE® Revised General Test: Quantitative Reasoning Sample QuestionsFiguresThis document includes figures, which appear on screen. Following each figure on screen is text describing that figure. Readers using visual presentations of the figures may choose to skip parts of the text describing the figure that begin with “Begin skippable figure description” and end with “End skippable figure description.”Mathematical Equations and ExpressionsThis document includes mathematical equations and expressions. Some of the mathematical equations and expressions are presented as graphics. In cases where a mathematical equation or expression is presented as a graphic, a verbal presentation is also given and the verbal presentation comes directly after the graphic presentation. The verbal presentation is in green font to assist readers in telling the two presentation-modes apart. Readers using audio alone can safely ignore the graphical presentations, and readers using visual presentations may ignore the verbal presentations.IntroductionThe revised Quantitative Reasoning section contains four types of questions: Multiple-choice Questions — Select One Answer ChoiceMultiple-choice Questions — Select One or More Answer ChoicesNumeric Entry QuestionsQuantitative Comparison QuestionsEach question appears either independently as a discrete question or as part of a set of questions called a Data Interpretation set. All of the questions in a Data Interpretation set are based on the same data presented in tables, graphs, or other displays of data. Below are descriptions, directions, and samples of each type of question.Multiple-Choice Questions —Select One Answer ChoiceThese questions are multiple-choice questions that ask you to select only one answer choice from a list of five choices.Sample QuestionsDirections: Select a single answer choice.Sample question 1 below is based on figure 1.Figure 1Begin skippable figure description.Figure 1 is a circle with center C.Two diameters of the circle are drawn, dividing the circle into 4 sectors. Two nonadjacent sectors are shaded, and the central angle of one of the unshaded sectors measures 160 degrees.End skippable figure description.1. Figure 1 above shows a circle with center C and radius 6. What is the sum of the areas of the two shaded regions?A. 7.5 piB. 6 piC. 4.5 piD. 4 piE. 3 piAnswer: D ( 4 pi)Sample question 2 below is based on figure 2.Figure 2Begin skippable figure description.Figure 2 shows the graph in the x y plane of the function f of x= the absolute value of 2x, end absolute value, + 4. There are equally spaced tick marks along the x axis and along the y axis. The first tick mark to the right of the origin, and the first tick mark above the origin, are both labeled 1.The graph of the function f is in the shape of the letter V. It is above the x axis and is symmetric with respect to the y axis.The lowest point on the graph of f is the point 0 comma 4 on the y axis.Going leftward from the point 0 comma 4 the graph of fis a line that slants upward, passing through the point negative 2 comma 8.Going rightward from the point 0 comma 4 the graph of f is a line that slants upward, passing through the point 2 comma 8.End skippable figure description.2. Figure 2 above shows the graph of a function f, defined byf of x = the absolute value of 2x, end absolute value, + 4 for all numbers x. For which of the following functions g defined for all numbers x does the graph of g intersect the graph of f?A. g of x = x minus 2B. g of x = x + 3C. g of x = 2x minus 2D. g of x = 2x + 3E. g of x = 3x minus 2Answer: E (g of x = 3x minus 2)Multiple-Choice Questions — Select One or More Answer Choices These questions are multiple-choice questions that ask you to select one or more answer choices from a list of choices. A question may or may not specify the number of choices to select.Sample QuestionsDirections: Select one or more answer choices according to the specific question directions.If the question does not specify how many answer choices to select, select all that apply.The correct answer may be just one of the choices or may be as many as all of the choices, depending on the question.No credit is given unless you select all of the correct choices and no others.If the question specifies how many answer choices to select, select exactly that number of choices.1. Each employee of a certain company is in either Department X or Department Y, and there are more than twice as many employees in Department X as in Department Y. The average (arithmetic mean) salary is $25,000 for the employees in Department X and is $35,000 for the employees in Department Y. Which of the following amounts could be the average salary for all of the employees in the company?Indicate all such amounts.A.$26,000B. $28,000C. $29,000D. $30,000E. $31,000F. $32,000G. $34,000Answer: A ($26,000) and B ($28,000)2. If f, g, and h are positive integers, f is a factor of g, and g is a factor of h, which of the following statements must be true?Indicate all such statements.A. f is a factor of g squared.B. f is a factor of gh.C. f is a factor of h minus g.Answer: A (f is a factor of g squared), B (f is a factor of gh.),and C (f is a factor of h minus g)Numeric Entry QuestionsQuestions of this type ask you either to enter the answer as an integer or a decimal in a single answer box or to enter it as a fraction in two separate boxes —one for the numerator and one for the denominator. In the computer-administered test, the computer mouse and keyboard are used to enter the answer.Sample QuestionsDirections: Enter your answer in the answer box(es) below the question.Equivalent forms of the correct answer, such as 2.5 and 2.50, are all correct. Fractions do not need to be reduced to lowest terms.Enter the exact answer unless the question asks you to round your answer.1. If x = 10 to the power negative 1, what is the value ofopen parenthesis, x + the fraction 1 over x, close parenthesis, times, open parenthesis, 1 over x, close parenthesis?Answer BoxAnswer: 1012. A university admitted 100 students who transferred from other institutions. Of these students, 34 transferred from two-year community colleges, 25 transferred from private four-year institutions, and the rest transferred from public four-year institutions. If two different students are to be selected at random from the 100 students, what is the probability that both students selected will be students who transferred from two-year community colleges?Give your answer as a fraction.Fraction answer boxesAnswer: 17 over 150 (or any equivalent fraction).Quantitative Comparison QuestionsQuestions of this type ask the examinee to compare two quantities —Quantity A and Quantity B — and then determine which of four statements describes the comparison.Sample QuestionsDirections: Compare Quantity A and Quantity B, using the additional information given, if any. Select one of the following four answer choices.A. Quantity A is greater.B. Quantity B is greater.C. The two quantities are equal.D. The relationship cannot be determined from the information given.A symbol that appears more than once in a question has the same meaning throughout the question.1.Quantity A: x squared + 1Quantity B: 2x, minus 1A. Quantity A is greater.B. Quantity B is greater.C. The two quantities are equal.D. The relationship cannot be determined from the information given.Answer: A (Quantity A is greater.)Sample question 2 below is based on figure 3.Figure 3Begin skippable figure description.Figure 3 shows parallelogram RSTU. Sides R U and S T are horizontal, with S T above, and slightly to the left of side R U. Diagonal S U, which extends from vertex S at the upper left of the parallelogram to vertex U at the lower right of the parallelogram, divides the parallelogram into two triangles, R S U and U S T; and the angle at vertex S into 2 adjacent angles R S U and U S T. The measure of angle R S U is x degrees, and the measure of angle U S T is y degrees.End skippable figure description.2.It is given that RSTU is a parallelogram.Quantity A: xQuantity B: yA. Quantity A is greater.B. Quantity B is greater.C. The two quantities are equal.D. The relationship cannot be determined from the information given.Answer: D (The relationship cannot be determined from the information given.) Data Interpretation SetsData Interpretation questions are grouped together and refer to the same table, graph, or other data presentation. These questions ask you to interpret or analyze the given data. The types of questions may be Multiple-choice (both types) or Numeric Entry.Sample QuestionsDirections: Questions 1 to 3 are based on the data in the following table.The table shows the percent change in monthly value of inventory at six businesses from April to June.Business Percent Change from April toMayPercent Change from May to JuneG +6 +8K +5 minus 5M +2 +12R +8 minus 5V +14 0Z +2 minus 10Note: Inventory values are determined at the end of each month.1. If the value of inventory at Business K was $30,000 for April, what was the value of inventory at Business K for June?A. $22,500B. $29,925C. $30,000D. $33,000E. $33,075Answer: B ($29,925)2. At Business M, the value of inventory for May was what percent of the value of inventory for June?Give your answer to the nearest 0.1 percent.% Answer box followed by percent signAnswer: 89.33. For which of the six businesses shown was the percent change in value of inventory from April to June greatest?A. GB. KC. MD. RE. VAnswer: A (Business G)Directions: Questions 4 to 6 are based on the data shown in figure 4.Figure 4Begin skippable figure description.The title of the data in figure 4 is “Workforce of Country X.” The data consists of a pie chart and a bar graph. The title of the pie chart is “Percent Distribution of Workforce by Employment Sector” and the title of the bar graph is “Workforce in the Service Sector by Area and Gender.”The percent distribution of the workforce by employment sector in the pie chart is as follows:Professional Sector 20%.Service Sector 15%Construction and Maintenance Sector 10%Production and Transportation Sector 15%Other Sector 15%Sales Sector 10%Management Sector 15%The bar graph shows the number of males and females in each of the five service sectors. The bar graph has horizontal bars. The graph has a horizontal axis labeled Millions of People, with vertical gridlines in multiples of 0.5 million, from 0.5 million to 4 million. Five Service Sector areas are listed along the vertical axis. The data in the bar graph is as follows:Health Care Sector, 0.5 million males and 2.75 femalesProtective Service Sector, a little under 2 million males and 0.5 million femalesFood Service Sector, a little under 3 million males and a little under 4 million femalesPersonal Care Sector, a little over 0.5 million males and about 2.75 million femalesOther Sector, a little under 3 milllion males and a little under 2 million femalesEnd skippable figure description.4. Approximately how many people are in the production and transportation sector of the workforce?A. 9 millionB. 12 millionC. 15 millionD. 18 millionE. 21 millionAnswer: E (21 million)5. In the workforce, the ratio of the number of males to the number of females is the same for the sales sector as it is for the protective service area of the service sector. Which of the following is closest to the number of females in the sales sector?A. 2.9 millionB. 3.6 millionC. 10.4 millionD. 11.1 millionE. 14.0 millionAnswer: A (2.9 million)。
GRE数学｜专项练习及解析｜概率
GRE数学｜专项练习及解析｜概率GRE数学专项练习的题目主要来自《官方指南》（OG）、《官方数学150》（ETS150）、鸡精和个别来源未知的题目（同样适合练习），接下来我会持续更新各种专项练习和题目解析。
概率是较为常考的一个考点，同时也经常会结合排列组合进行考察，所以练习概率的同时，也有必要掌握和练习排列组合部分，这里附上两篇推送：《马雨：GRE数学考点梳理——排列组合》《GRE数学｜专项练习及解析｜排列组合》接下来是题目+解析，如果对你有所帮助，欢迎点赞转发注：比大小的题目四个选项含义和顺序固定，即：1.2.3.4.5.6.7.8.9.10.11.12.13. A，B都是独立事件，A发生的概率是45%，问A和B同时发生的最大概率是多少?14. A和B是独立事件，A发生的概率是0.6，B发生的概率是0.8 Quantity A：The probability that A or B, or both will occur Quantity B：0.92 15. A俱乐部20男，40女，B俱乐部男至少有7人，也有女。
从A和B俱乐部中各选一个人，两个俱乐部选出的人同时是男生的概率小于等于1/15，以下哪些选项一定正确? （不定项选择题）A. The number of people in group B is greater than 34 B. The number of girls in group B is greater than 32C. The number of girls in group B is less than 3416. 有60个球，里面有$3和$5的两种，其中$3的球总价为$72，求随意抽一个球抽到$5的球的概率17. 第一次抽到红球的概率是5/8，第一次抽不中的情况下，第二次抽到红球的概率是2/3，求第一次或第二次或两次都抽到红球的概率？18. 从6个男生和4个女生中选4个人，刚好2男2女的概率是多大?19. 一共有7个球，其中只有1个是红色的，不放回的抽取，抽到红球为止Quantity A: 第3次抽到红球的概率Quantity B: 第4次抽到红球的概率20. 从1，2，3，4，5中同时选两个数，问选出来两个数相乘是odd number的概率是多少？21. 用1，2，3，4，5这个五个数字组成一个三位数和一个两位数，数字都不可重复使用。
GRE阅读真题之OGPassage5-7答案解析
GRE阅读真题之OGPassage5-7答案解析为了帮助大家在备考gre的时候能够练习更多的阅读题目，下面小编给大家带来GRE阅读真题之OG Passage 5-7答案解析，希望大家喜欢!GRE阅读真题之OG Passage 5OG-1Passage 5Since the Hawaiian Islands have never been connected to other land masses, the great variety of plants in Hawaii must be a result of the long-distance dispersal of seeds, a process that requires both a method of transport and an equivalence between the ecology of the source area and that of the recipient area.There is some dispute about the method of transport involved. Some biologists argue that ocean and air currents are responsible for the transport of plant seeds to Hawaii. Yet the results of flotation experiments and the low temperatures of air currents cast doubt on these hypotheses. More probable is bird transport, either externally, by accidental attachment of the seeds to feathers, or internally, by the swallowing of fruit and subsequent excretion of the seeds. While it is likely that fewer varieties of plant seeds have reached Hawaii externally than internally, more varieties are known to be adapted to external than to internal transport.1. The author of the passage is primarily concerned withA. discussing different approaches biologists have taken to testing theories about the distribution of plants in HawaiiB. discussing different theories about the transport of plant seeds to HawaiiC. discussing the extent to which air currents are responsiblefor the dispersal of plant seeds to HawaiiD. resolving a dispute about the adaptability of plant seeds to bird transportE. resolving a dispute about the ability of birds to carry plant seeds long distances2. The author mentions the results of flotation experiments on plant seeds (lines 7–8) most probably in order toA. support the claim that the distribution of plants in Hawaii is the result of the long-distance dispersal of seedsB. lend credibility to the thesis that air currents provide a method of transport for plant seeds to HawaiiC. suggest that the long-distance dispersal of seeds is a process that requires long periods of timeD. challenge the claim that ocean currents are responsible for the transport of plant seeds to HawaiiE. refute the claim that Hawaiian flora evolved independently from flora in other parts of the worldGRE阅读真题之OG Passage 6OG-1Passage 6I enjoyed A Dream of Light & Shadow: Portraits of Latin American Women Writers for the same reasons that, as a child, I avidly consumed women’s biographies: the fascination with how the biographical details of another female’s life are represented and interpreted.A Dream offers a rich read, varied in both the lives and texts of the women portrayed, and the perspectives and styles of the sixteen essayists. Yet, as an adult, I have come to demand of any really “great” book a self-consciousness about the tenuous nature of representations of reality, a critical contextualization offlorid detail, and a self-awareness of the role of ideology in our lives. In these critical senses, A Dream is inadequate.For the following question, consider each of the choices separately and select all that apply.1. The author of the passage suggests that A Dream falls short in which of the following respects?A. It does not appear to recognize that representations of reality can be unreliable.B. It seems to focus on stylistic variety at the expense of accuracy of detail.C. It offers a wealth of detail without sufficient critical examination of that detail.2. Which of the following best describes the function of the second sentence (“A Dream . . . essayists”) in the context of the passage as a whole?A. To give examples of how A Dream presents fascinating portraits that display awareness of the tenuous nature of representations of realityB. To elaborate on ho w A Dream fulfills the author’s childhood criteria for a pleasurable bookC. To suggest that the author enjoyed A Dream for reasons more sophisticated than the reasons she enjoyed certain books as a childD. To illustrate ways in which the author finds A Dream to be inadequate in certain critical sensesE. To imply that A Dream is too varied in focus to provide a proper contextualization of the biographical details it offers GRE阅读真题之OG Passage 7OG-1Passage 7During the day in Lake Constance, the zooplankton D. hyalina departs for the depths where food is scarce and the water cold.D. galeata remains near the warm surface where food is abundant. Even though D. galeata grows and reproduces much faster, its population is often outnumbered by D. hyalina.1. Which of the following, if true, would help resolve the apparent paradox presented above?A. The number of species of zooplankton living at the bottom of the lake is twice that of species living at the surface.B. Predators of zooplankton, such as whitefish and perch, live and feed near the surface of the lake during the day.C. In order to make the most of scarce food resources,D. hyalina matures more slowly than D. galeata.D. D. galeata clusters under vegetation during the hottest part of the day to avoid the Sun’s rays.E. D. galeata produces twice as many offspring per individual in any given period of time as does D. hyalina.GRE官方指南(OG)中的阅读真题答案Passage 第一题第二题第三题第四题5 B D6 AC B7 BGRE阅读真题之OG Passage 5-7答案解析。
GRE数学考试的经典例题讲解
GRE数学考试的经典例题讲解GRE数学考试的经典例题讲解考生在备考GRE数学考试的过程中，可以多了解一些比较经典的例题。
下面就让店铺给大家讲解GRE数学考试的比较经典的部分例题吧，希望能对你有帮助!GRE数学的经典例题：dollar amountIf the dollar amount of sales at Store P was $800,000 for 2006, what was the dollar amount of sales at that store for 2008 ?A $727,200B $792,000C $800,000D $880,000E $968,000直接算，800000*(1+10%)*(1-10%)=792000，即B2)At Store T, the dollar amount of sales for 2007 was what percent of the dollar amount of sales for 2008 ?Give your answer to the nearest 0.1 percent.___________%直接算，1/(1-8%)=108.7%(约等于)3)Which of the following statements must be true?Indicate all such statements.A For 2008 the dollar amount of sales at Store R was greater than that at each of the other four stores.B The dollar amount of sales at Store S for 2008 was 22 percent less than that for 2006.C The dollar amount of sales at Store R for 2008 was more than 17 percent greater than that for 2006.本题A选项一看到就可以排除了，涉及到两个店的绝对量的比较，这个不确定，没有告诉绝对值。