TT GWD 1-2

grossmun

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？

laststraws

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

soupset

为什么是3*2*1？？？

难道我翻译错了

请问这道题怎么翻译····