A certain jar contains only"b" black marbles, 'W" white marbles, and "r" red marbles. If one marble is to be chosen at random from the jar, is the porobability that the marble chosen will be red greater than the probability that the marble chosen will be white?
(1) r/(b+w) > w/(b+r)
(2) b-w>r
答案為A作者: xiexiang 时间: 2010-10-25 21:09
the porobability that the marble chosen will be red :r/(r+b+w)
the probability that the marble chosen will be white:w/(r+b+w)
the porobability that the marble chosen will be red greater than the probability that the marble chosen will be white:r/(r+b+w)>w/(r+b+w)
