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?
A. 0
B. 1/9
C. 2/9
D. 1/3
E. 1
答案选c 为什么不是B呢?
总共有 3^3种情况 其中 passenger will ride in each of the 3 cars的情况数为 3*2*1
so AN=3*2*1/3*3*3=2/9
为什么是3*2*1???
难道我翻译错了
请问这道题怎么翻译····
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