GRE数学(Barron模考)每日一题 第42期
日期:2014-11-09 10:47
(单词翻译:单击)
GRE数学试题
A certain roller coaster has 3 cars, and a passenger is equally likely to ride in any 1 of the 3 cars each time that passenger rides the roller coaster. If a certain passenger is to ride the roller coaster 3 times, what is the probability that the passenger will ride in each of the 3 cars?
参考答案
P=(3*2*1)/(3*3*3)=2/9
重点单词