GRE數學(xué)部分對于考生來(lái)說(shuō)是難度相對較低的，考生也期望著(zhù)能夠在這個(gè)部分表現出色拿到高分滿(mǎn)分以提升總成績(jì)。本文將GRE 數學(xué)各大高頻考點(diǎn)題型的具體講解和解題思路剖析，確?？忌辉诤?jiǎn)單數學(xué)部分意外失分，順利拿到高分滿(mǎn)分！
題目1. 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. 3/4
答案：C
解析：本題因為奇數和偶數個(gè)數相同，和也只有兩種方式，所以三個(gè)數的和為奇數的可能性為 1/2。也可以考慮從這 100 個(gè)數中任取三個(gè)數的奇偶，可能性為：奇奇奇，奇偶偶，奇奇偶和偶偶偶，其中奇奇奇和奇偶偶兩種情況的和為奇數，所以也得到可能性為 1/2
2. 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%
解析：A 和 B 的并集為：54% 48%-30%=72%，所 C 為 28%
3. 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 electric record; For policies having incorrect electric record, 75% also having incorrect paper 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. 0.92
答案：B
解析：設總數為 x，設 incorrect paper record 有 y, incorrect electric record 有 z，則：
x · y · 60%=3% · x y=5%
x · z · 75%=3% · x z=4%
則，兩者至少有一個(gè)錯誤的百分比為 5% 4%-3%=6%，所正確答案為 94%
A. 1.6
B. 3.2
C. 1.5
D. 1.25
E. 1.15
答案：D
解析：1/20 ( 14-2.5 ) 1/30 ( 14-x ) =1，得出 x=1.25
5. The probability of A is 60% and the probability of B is 50%, what is the most possible probability that neither A nor B would happen?B. 0.40
D. 0.55
E. 0.68
解析：劃出圖表來(lái)可以一目了然：A， B 均不發(fā)生的大概率為 40%，小概率為 0. 因此選 B
