会计考友 发表于 2012-8-15 12:55:17

新GRE数学要点:AT least One

 AT least One   If probability of event A happening is p and event B happening is q, then the probability that at least one of them happens is (p+q).
  Example:
  There are 20 quarters, 33 nickels, and 47 pennies in a jar. The probability that a randomly selected coin is a quarter= 20/(20+33+47)=20/100=0.2 and the coin is nickel = 33/100 =0.33.The probability it is either a quarter or a nickel = 0.2+0.33=0.53.
  Remember:
  The events needs to be mutually exclusive, that is if one happens the other cannot happen: a coin is either a quarter or nickel but not both.
  由于美国数学基础教育的难度增加导致数学考试越来越难,但新gre数学复习考点都是高中时候学到的知识点,考生不要过于紧张,把基本概念弄明白,再记住一些新版gre数学必备的词汇,那么相信新版gre数学应该没有问题。
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