GRE数学难题解析(1)
GRE考试题目及解析
GRE考试题目及解析GRE考试题目及解析1、2解：不确定2、X~3 * y = 10 ~6 (y 1)，问X 与10~2比大小解：x=10~2/y~1/3y1则y~1/31 所以还是10~2大选B3、数列：a1=3，a2=6，a(n)= a(n-1)/a(n-2)，问：a(150)=?解：3，6，2，1/3，1/6，1/2，3，6，(每6次一个循环，答案应当是1/2吧)另一版本：前人几经有误，我的是：a1=2，a2=6，an=a(n-1)/a(n-2)，求a1502，6，3，1/2，1/6，1/3 ，2，6，3，…所以我的答案是1/3(大家看清晰A1的值，自己推断吧)4、125w+25x+5y+z=264，x，y，z，w，are nonnegative integrate，and no more than 5，what is w+x+y+z?解：用短除法把256写成五进制就是2024，则得到x+y+z+w=2+0+2+4=85、a * x平方+B*X+k=0(a和b已知，k未知)，给出一个X的.值，问另一个。
简洁，解出K后，再解出X26、a，b，c，-5，-10的平均数和a，b，c，5，10的平均数之差是多少?解：在考场遇到时看清晰谁在前。
答案是-6 ，或许是6。
7、F(X)=2的2X-1方，求F(3+X)F(3-X)解：2的10次方8、-7解：当X= -7 ，Y= 0 时最大，49。
9、有个公式很重要。
求M到N之间是Q的倍数的数有多少个?公式是：[(该范围内Q的最大倍数-该范围内Q的最小倍数)/Q ] +1今日我遇到两个这样的题，多亏有这个公式，要不然就费劲了10、一个数，被9整除得x1+x2+x3，被12整除得x2+x3，则这个数至少为?能被x1整除?答案：369(x1+x2+x3)=12(x2+x3) x1=3(x2+x3)……、、11、数列a1，a2，、、、a10、除了第一项外的各项都是其前一项的1/2。
GRE数学难题
GRE数学--难题解析（一）1. On a certain number line, if -7 is a distance of 4 from n and 7 is a distance of 18 from n then n=(A) 25 (B) 11 (C)- 3 (D) 11 (E)-112. The diagram represents a rectangular garden. The shaded regions are planted in flowers, and the unshaded region is a walk 2 feet wide. All angles are right angles. The sum of the of the feet shaded regions 2,800 square areas3.The map shows the only roads that connect the four towns and shows the distance along each road.The road distance between Austen The road distance between Coaltownand Seburg and Woodland4.How many positive integers less than 20 are equal to the sum of a positive multiple of 3 and a positive multiple of 4?(A) Two (B) Five (C) Seven (D) Ten (E) Nineteen5.Which of the following symbols should be substituted for to make both of thestatements above true for all integers n such that -2< n≤3?(A) ≤ (B) < (C) = (D) > (E) ≥6.In a soccer league, If there were 10 teams and each team played each of the other teams 16 times, how many games did each team play?(A) 144 (B) 140 (C) 134 (D) 125 (E) 1067.In 1984 median income for a person in the 55-64 age category was in which of the following intervals?(A) less than $10,000 (B) $10,000-$19,999 (C) $20,000-$24,999(D) $25,000-$34,999 (E) $35,000-$49,999A sample of employees were tested on data-entry skills for one hour, and the number of errors (x) they made and the percent of employess (p) making x errors were recorded as follows.8. What was the median number of errors in the sample?(A) 3 (B) 3.5 (C) 4 (D) 4.5 (E) It cannot be determined from the information given.d=7.56872 and d1 is the decimal expression for d rounded to the nearest thousandth.9. The number of decimal places where d and d1 differ 410. In a certain country, a person is born every 3 seconds and a person dies every 10 seconds. Therefore, the birth and death rates account for a population growth rate of one person every11. Of the positive integers that are multiples of 30 and are less than or equal to 360, what fraction are multiples of 12?12. The figure above shows a large square formed by fitting three L-shaped tiles and one small square title together. If a rectangular floor 10 feet by 12 feet is to be tiled in large squares of this design, how many L-shaped tiles will be needed?(A) 810 (B) 405 (C) 270 (D) 135 (E) 4513. The daily rate for a hotel room that sleeps 4 people is $39 for one person and x dollars for each additional person. If 3 people take the room for one day and each pays $21 for the room, what is the value of x?(A) 6 (B) 8 (C) 12 (D) 13 (E) 2414. A positive integer with exactly two different divisors greater than 1 must be(A) a prime (B) an even integer (C) a multiple of 3(D) the square of a prime (E) the square of an odd integerx>zy>z15. x+y zx > y and xy≠02AF=AB=BD=DE=AE17. The sum of the area of triangular The area of rectangularregion ABF and area of region BCEFtriangular region CDE18. Each of the following numbers has two digits blotted out. Which of the numbers could be the number of hours in x days, where x is an integer?(A)25, 06(B)50, 26(C)56, 02(D)62, 50(E)65, 2020. The median score for the class is(A)76 (B)77 (C)78 (D)79 (E)8021. If 5 points were added to each score, which of the following would NOT be affected?(A)The highest score(B)The mean for all scores(C)The median for the seniors' scores(D)The mode for the juniors' scores(E)The standard deviation for all scores22. If the mean score for the juniors were known, which of the following could be calculated from the information given?I. The range of the scores for the seniorsII. The median score for the juniorsIII. The mean score for the seniors(A)None (B)I only (C)III only (D)I and II (E)II and III23. If in an experiment the probabilities of obtaining the valuesare, respectively, then the expected value is definedas For the values and their correspondingprobabilities in the table above, what is the expected value?(A)350 (B)320 (C)300 (D)270 (E)25024. The standard deviation of the sample The standard deviation of the sample measurements 0, 1, 2, 4, and 8 measurements 0, 1, 3, 5, and 925. What is the total number of different 5-digit numbers that contain all of the digits 2, 3,4,7 and 9 and in which none of the even digits occur next to each other?(A)72 (B)100 (C)120 (D)60 (E)48Water is to be poured at a rate of 2.5 gallons per minute into a 500-gallon tank that initially contains 50 gallons of water.28. The percent of the tank's capacity 60 percentthat will be filled 1 hour after waterbegins to be poured in29. In the figure above, if x, y, and z are integers such that x<y<z, then the least and the greatest possible values of x+z are(A)59 and 91 (B)69 and 135 (C)91 and 178 (D)120 and 135 (E)120 and 17830. The figure above shows the dimensions of rectangular box that is to be completely wrapped with paper. If a single sheet of paper is to be used without patching, then the dimensions of the paper could be(A)17 in by 25 in (B)21 in by 24 in (C)24 in by 12 in (D)24 in by 14 in(E)26 in by 14 in31. In the table above, what is the least number of table entries that are needed to show the mileage between each city and each of the other five cities?(A)15 (B)21 (C)25 (D)30 (E)3632. A store currently charges the same price for each towel that it sells. If the current price of each towel was to be increased by $1, 10 fewer of the towels could be bought for $120, excluding sales tax. What is the current price of each towel?(A)$ 1 (B)$ 2 (C)$3 (D)$ 4 (E)$ 12GRE数学--难题解析（二）33. Pat will walk from intersection X to intersection Y along a route that is confined to the square grid of four streets and three avenues shown in the map above. How many routes from X to Y can Pat take that have the minimum possible length? (A)Six (B)Eight (C)Ten (D)Fourteen (E)Sixteen34．In an insurance company, each policy has a paper record and an electric record. For those policies having incorrect paper record, 60% also having incorrect electricrecord; For those policies having incorrect electric record, 75% also having incorrect electric record. 3% of all policies have both incorrect paper and incorrect electric records. If we randomly pick out one policy, what's the probability that the one having both correct paper and correct electric records?(A)0.80 (B)0.94 (C)0.75 (D)0.88 (E)0.9235. There are 1200 respondents to a poll, each favoring their preference for candidates A, B,and C. 54% favored A, 48% favored B, and 42% favored C, and there is 30% favored both A and B. what's the largest possible number of respondents favoring C, but not C & B, nor C & A?(A)25% (B)30% (C)28% (D)38% (E)40%36. Out of 100 ladies attending the church fete, 85 had a white handbag; 75 had black shoes;60 carried an umbrella; 90 wore a ring. How many ladies must have had all four items?(A)15 (B) 35 (C)5 (D)10 (E)2537. The sergeant had fewer than 500 men to line up on parade. He tried arranging them in rows of three, but found there was one leftover. Then he tried them in rows of four, then five and six, but always there was one leftover. Finally, he tried them in rows of seven, and, to his relief, saw that the rows were exactly even. How many soldiers were lined up on parade?(A)308 (B)241 (C)296 (D)245 (E)30138. The vicar returns from his allotment with a small bag of tomatoes. To the first parishioner he meets he gives half the tomatoes plus half a tomato, to the second he gives half what he has left plus half a tomato and to the third he gives half what he has left plus half a tomato. He has then distributed all his bag of tomatoes. How many tomatoes did he initially have in the bag?39. The median salary of A, B, C, D, E is $20000, the range of these five people's salary is less than $50000. We have already known that the salaries of A, B, C are $20000, $40000, $50000, respectively. What is the probable average salary of these five people?(A)$20000 (B)$32000 (C)$18000 (D)$23000 (E)$3100040. 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。
【小站教育】GRE数学解题大全
【小站教育】GRE数学解题大全GRE数学解题大全目录GRE数学解题大全 (1)代数与几何部分 (2)概率论部分 (5)1.排列(permutation): (5)2．组合(combination): (5)3．概率 (5)统计学部分 (8)1.mode（众数） (8)2.range（值域） (8)3.mean（平均数） (8)4.median（中数） (8)5.standard error（标准偏差） (9)6.standard variation (9)7.standard deviation (9)8.the calculation of quartile(四分位数的计算) (9)9．The calculation of Percentile (10)10.To find median using Stem-and-Leaf (茎叶法计算中位数)(11)11．To find the median of data given by percentage(按比例求中位数) (12)12：比较,当n<1时，n，1，2 和1，2,3的标准方差谁大 (13)13.算数平均值和加权平均值 (13)14.正态分布题. (13)15．正态分布 (13)GRE数学符号与概念 (16)常用数学公式 (19)精讲20题 (20)GRE数学考试词汇分类汇总 (26)代数-数论 (26)代数-基本数学概念 (27)代数-基本运算, 小数,分数 (27)代数-方程,集合,数列等 (28)几何-三角 (29)几何-平面, 立体 (29)几何-图形概念 (30)几何-坐标 (31)商业术语,计量单位 (31)GRE数学考试词汇首字母查询 (32)代数与几何部分1.正整数n有奇数个因子,则n为完全平方数2.因子个数求解公式:将整数n分解为质因子乘积形式,然后将每个质因子的幂分别加一相乘.n=a*a*a*b*b*c则因子个数=(3+1)(2+1)(1+1)eg. 200=2*2*2 * 5*5 因子个数=(3+1)(2+1)=12个3.能被8整除的数后三位的和能被8整除;能被9整除的数各位数的和能被9整除.能被3整除的数,各位的和能被3整除.4.多边形内角和=(n-2)x1805.菱形面积=1/2 x 对角线乘积6.欧拉公式：边数=面数+顶点数-28.三角形余玄定理C2=A2+B2-2ABCOSβ,β为AB两条线间的夹角9.正弦定理:A/SinA=B/SinB=C/SinC=2R(A,B,C是各边及所对应的角,R是三角形外接圆的半径)10.Y=k1X+B1,Y=k2X+B2，两线垂直的条件为K1K2=-111.N的阶乘公式:N!=1*2*3*....(N-2)*(N-1)*N 且规定0!=1 1!=1Eg:8!=1*2*3*4*5*6*7*812. 熟悉一下根号2、3、5的值sqrt(2)=1.414 sqrt(3)=1.732 sqrt(5)=2.23613. ...2/3 as many A as B: A=2/3*B...twice as many... A as B: A=2*B14. 华氏温度与摄氏温度的换算换算公式:(F-32)*5/9=CPS.常用计量单位的换算:（自己查查牛津大字典的附录吧）练习题:1：还有数列题：a1=2，a2=6，a n=a n-1/a n-2，求a150.解答: a n=a n-1/a n-2,所以a n-1=a n-2/a n-3,带入前式得a n=1/a n-3,然后再拆一遍得到a n=a n-6,也就是说,这个数列是以6为周期的,则a150=a144=...=a6,利用a1,a2可以计算出a6=1/3.如果实在想不到这个方法,可以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,就可以知道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=54<623：那道费波拉契数列的题:已知,a1=1 a2=1 a n=a n-1+a n-2，问a1,a2,a3,a6四项的平均数和a1,a3,a4,a5四项的平均数大小比较。
GRE考试的数学难题总结
The love is deep and ruthless, and the heart is not old.精品模板助您成功！（页眉可删）GRE考试的数学难题总结1. n是integer, n^2+n被2除，余数与0比较，答案相等，因为n^2+n=n(n+1)，必为偶数2. 商品X的价格是$35,商品Y的价格至少是X的2/3，问Y 的价格与$24比较，不能确定3 1/11+1/12+1/13+1/14+1/151/34. 某种溶液浓度为125gram per liter, 转换成 ounce per gallon,求表达式已知 1 ounce=28.__x gram and 1 gallon=3.875 liter5. (x-3)/(x-1)=0，比较x与1(没说x≠1) 大于6. 满足方程x/13+y/39=1的正整数对(x,y)有多少对。
(12)7. 体重超过225的人当中血脂超过300的人占体重超过225的人的percentage? 4/9=44% ：在所有被检测人中任意抽查一个人,血脂和体重都超过200的概率?8 .图题，横坐标是胆固醇量，纵坐标是体重， q1有问体重小与170，胆固醇高于20的比例， q2 体重大于190或胆固醇小于19的比例，注意相加后减去共有的。
9. 另一道是统计题，列了一个表，说的是城市里养狗的情况，0只的有多少家，1只的多少，。
，养了5只以上的多少，求城市里平均每家养狗数。
这里要注意加权平均的时候，养了五只以上的(设有10家)，那就按每家养5只来加权。
然后算出来的记得是1.7左右，但答案里只有1.5与2，我就选了2。
10. #两个数列1，2，3，4，5......M1，2，3，4，5......N每个数列中均为连续整数。
M为EVEN，N为ODD比较第一个数列中奇数的PERCENTAGE与第二个数列中偶数的PERCENTAGE(前者大于后者)11. 有一道图表题，有一个饼图，一个表。
2024年GRE考试数学真题深度解读
2024年GRE考试数学真题深度解读在2024年的GRE考试中，数学部分的题目一直是考生们比较关注的一个方面。
本文将对2024年GRE考试数学部分的真题进行深度解读，帮助考生们更好地应对这一考试内容。
以下是对一些典型题目的解析和详细讲解。
题目一：计算方程的解设方程2x + 5 = 15，求x的解。
解析：这是一个简单的一元一次方程，可以通过移项和化简求解。
将方程变形，得到2x = 15 - 5，进一步计算可得2x = 10。
最后，将方程化简为x = 10 / 2，即x = 5。
因此，方程2x + 5 = 15的解为x = 5。
题目二：几何图形的面积计算已知一个正方形的周长等于24cm，求其面积。
解析：正方形的周长等于4条边的长度之和，因此设每条边长为x，则有4x = 24。
将方程化简可得x = 24 / 4，即x = 6。
正方形的面积等于边长的平方，因此面积为6 * 6 = 36 平方厘米。
所以，该正方形的面积为36平方厘米。
题目三：概率计算一枚硬币投掷三次，出现正面的次数大于等于2次的概率是多少？解析：对于一次硬币投掷，它的结果只有两种可能：正面朝上或反面朝上，因此该事件是一个二项分布。
投掷三次硬币，出现正面大于等于2次的情况有3种可能情况：正正正、正正反和正反正。
因此，概率 = P(正正正) + P(正正反) + P(正反正)。
每一种可能性的概率为1/2 * 1/2 * 1/2 = 1/8。
将所有概率相加，得到概率为3/8。
所以，出现正面大于等于2次的概率是3/8。
通过对以上三个题目的解析，可以看出2024年GRE考试数学部分的难度适中，考察的内容主要涵盖了代数、几何和概率等基础知识。
在备考过程中，考生们应该注重对这些基础知识的扎实掌握，并且要能够将这些知识应用于解决实际问题。
除了对基础知识的理解和掌握外，考生们还需要注重解题的方法和步骤。
不同的题目可能需要不同的解题思路，因此在备考中要注重总结各种解题方法，并且进行反复练习和巩固。
新GRE数学考试难题讲解
新GRE数学考试难题讲解智课网GRE备考资料新GRE数学考试难题讲解本文是新东方在线为广大考生整理的新GRE数学考试难题讲解，希望帮助大家解决GRE考试难题，取得好的成绩。
1 .x+y=5&2x+2y=8之间最短距离与1比较 l5. 从一堆6个什么东东(blesket?不认识的单词)里取4个共会有15种不同的可能，如果从8个里面取4个会比从6个里面取多多少种可能?我选的是55.这题有点怪，不知为什么它还要把15说出来。
难道是我理解有误?6 .一个表3分钟慢一秒钟，问慢3分钟要过多少分种?540分钟。
7. 3/0.0001 与 3/0.000099 比大小。
8. 在一个图表题里考到了median。
这题比较不好做，还是罗马数字题。
是有关选民选举的比例，两块饼饼统计图，一饼是参选人x,y的支持率，另一块是选民们的收入income (?)。
从图中收入少于3000的选民有58% ，所以说选民收入median在收入少于3000的里面。
9. 有一题问下面这个数里能找出的最2的最大次方的factor 是多少?(2 )(12)(18 )，指数可能不是这个了，不过意思是这个意思。
10. 图表题,1992年总和是50,96年是60,每年至少增长1,问最大的年增长:7.011. n个数从小到大排列，求(n-1)/4，设商为i，余数为j ,则可求得1st Quartile为：(第i+1个数)*(4-j)/4+(第i+2个数)*j/412. 4个*，2个·的排列方式 15(=)13 .5双袜子，同时去2只，刚好配对的概率。
1/914. 40人说French,60人说Russian,80人说Italy,说两种语言的有50人,说三种语言的有 10人. 共有125人,问不说这些语言的有几人.Key:125-(40+60+80-50-10*2)=1515 .等腰直角三角形边长2加2倍根号2，求面积。
16. 某种溶液浓度为125gram per liter, 转换成 ounce per gallon,求表达式.已知 1 ounce=28.xxx gram and 1gallon=3.875 liter.7. x,y,z 均方差为d, 求x+10,y+10,z+10的均方差 (d)18. 1的概率是0.8,2的概率是0,6,问是1或是2或是both的概率,1-0.6*0.8(数字瞎编)=0.92.19. 还有一组测量数据中,12.1比mean低1.5个标准差,17.5比mean高3.0个标准方差.问mean是多少.13.9(设标准差为X 12.1+1.5X=M，17.5-3X=M) 20. 1-10中选出两个数，可重复，问是都是偶数的概率。
2023年GRE考试资料分析数学题及答案
2023年GRE考试资料分析数学题及答案
引言
本文档旨在分析2023年GRE考试的数学题目及其答案。
通过对这些题目的深入剖析，考生将能够更好地理解数学部分的考试内容与难度。
数学题目分析
以下是一些2023年GRE考试数学题目的分析：
1. 题目：在平面直角坐标系中，两条直线l和m的斜率分别为3和-2，而y轴截距分别为4和-5。
求直线l和直线m的交点坐标。
- 答案：直线l和直线m的交点坐标为(3, 4)。
2. 题目：有一个等腰直角三角形，其中两条边的长度分别为5和5√2。
求三角形的斜边长度。
- 答案：三角形的斜边长度为5√3。
3. 题目：一个中装有30个红球和40个蓝球。
从中随机取出一个球，求取得红球的概率。
- 答案：取得红球的概率为3/7。
4. 题目：已知f(x) = 2x^2 + 3x + 1，求f(2)的值。
- 答案：f(2)的值为15。
5. 题目：若a + b = 7，且a^2 + b^2 = 29，求ab的值。
- 答案：ab的值为-6。
结论
通过本文档对2023年GRE考试的数学题目进行分析，我们可以看出其中的一些常见题型和解题方法。
对于考生来说，通过熟悉并掌握这些题目的解题思路和答案，将有助于提高他们在数学部分的得分。
同时，这也提醒考生在备考过程中要牢固掌握数学基础知识，并注重对题目要求的准确理解及逻辑推理能力的培养。
2023年GRE数学考试题目及解析(完整打印版)
2023年GRE数学考试题目及解析(完整打印版)第一部分：数学基础1. 题目：求解方程给定方程：2x + 5 = 11，求解x的值。
解析：将方程重写为：2x = 11 - 5。
计算得出：2x = 6。
继续计算得出：x = 6 / 2。
最终解得：x = 3。
2. 题目：求解等差数列的和已知等差数列的首项为3，公差为2，共有10个项，求该等差数列的和。
解析：首先，可以使用公式求解等差数列的和：Sn = n/2 * [2a + (n-1)d]。
代入已知值：n = 10，a = 3，d = 2。
计算得出：Sn = 10/2 * [2*3 + (10-1)*2]。
继续计算得出：Sn = 5 * (6 + 18)。
最终解得：Sn = 120。
第二部分：几何图形3. 题目：计算三角形面积已知三角形的底边长为5，高为8，求三角形的面积。
解析：三角形的面积可以通过公式计算：A = 1/2 * 底边长 * 高。
代入已知值：底边长 = 5，高 = 8。
计算得出：A = 1/2 * 5 * 8。
最终解得：A = 20。
4. 题目：计算圆的周长已知圆的半径为4，求圆的周长。
解析：圆的周长可以通过公式计算：C = 2 * π * 半径。
代入已知值：半径 = 4，π取3.14。
计算得出：C = 2 * 3.14 * 4。
最终解得：C = 25.12。
第三部分：数据分析5. 题目：计算平均数已知一组数据为：5, 8, 6, 12, 9，求这组数据的平均数。
解析：计算平均数的公式为：平均数 = 数据总和 / 数据个数。
代入已知值：数据总和 = 5 + 8 + 6 + 12 + 9，数据个数 = 5。
计算得出：平均数 = (5 + 8 + 6 + 12 + 9) / 5。
最终解得：平均数 = 8。
6. 题目：计算中位数已知一组数据为：2, 5, 8, 11, 15，求这组数据的中位数。
解析：首先对数据进行排序：2, 5, 8, 11, 15。
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GRE数学难题解析（1）
1.Sixty-eight people are sitting in 20 cars and each car contains at most 4 people. What is the maximum possible number of cars that could contain exactly 1 of the 68 people?
A.2
B.3
C.4
D.8
E.12
2.if n is any prime number greater than 2, which of the following cannot be a prime number?
A.n-4
B.n-3
C.n-1
D.n+2
E.n+5
3.In 1988 Mr. Smith’s annual income was greater than Mrs. Smith’s annual income. In 1989 Mr. Smith’s annual income decreased by p percent, whereas Mrs. Smith’s annual income increased by p percent. (p>0)
Column A: Mr. and Mrs. Smith’s combined annual income in 1988
Column B: Mr. and Mrs. Smith’s combined annual income in 1989
4.How many integers between 101 and 201 are equal to the square of some integer?
A. Two
B. Three
C. Four
D. Five
E. Six
5. The price of a certain stock was 12*1/2 dollars per share.
The price increased x percent to 15*5/8 dollars per share.
Column A: x
Column B: 20
6. The “reflection” of a positive integer is obtained by reversing its digits. For example, 321 is the reflection of 123. The difference between a five-digit integer and its reflection must be divisible by which of the following?
A.2
B.4
C.5
D.6
E.9
7. Column A: 1/(1-0.03)
Column B: 1.03
8.The original value of machine X is V dollars, while the original value of machine Y is 2V dollars. Both machines depreciate in value at a constant rate of 10 percent of their original value per year.
Column A: The value of machine X after 3 years
Column B: The value of machine X after 6 years
9. If n is an odd integer, which of the following is the square of the next larger odd integer?
A. n*n+1
B. n*n+4
C. n*n+2n+1
D. n*n+4n+1
E.n*n+n+1
10. If 55 percent of a group of people have brown hair and 80 percent of the same group do not have red hair, what fraction of those who do not have brown hair red hair?
A. 1/4
B.4/11
C.4/9
D.5/9
E.4/5。