A certain jar contains 100 jelly beans: 50 white, 30 green, 10 yellow, 5 red, 4 purple, and 1 black. If a jelly bean is to be ch

admin2009-05-19  79

问题 A certain jar contains 100 jelly beans: 50 white, 30 green, 10 yellow, 5 red, 4 purple, and 1 black. If a jelly bean is to be chosen at random, what is the probability that the jelly bean will be neither purple nor red?

选项 A、0.09
B、0.11
C、0.55
D、0.91
E、0.96

答案D

解析 一个罐子中装有100粒果冻豆:50粒白的,30粒绿的,10粒黄的,5粒红的,4粒紫的,l粒黑的。若从中随机挑出一粒果冻豆,问该粒果冻豆既不是紫色,又不是红色的概率是多大?
解:本题的正确答案是(D)。因为红色有5粒,紫色有4粒,且挑出任一粒的概率相同,所以随机挑出的果冻豆既不是红色又不是紫色的概率为:(100-9)/100=0.91
转载请注明原文地址:https://jikaoti.com/ti/uSdYFFFM
本试题收录于: GRE QUANTITATIVE题库GRE分类
0

最新回复(0)