Question 1002860
1/3 of the time she will pick the right first door.
1/3 of the time she will pick the right second door.
1/3 of the time she will pick the right third door.


her probability of winning is therefore 1/3 * 1/3 * 1/3 = 1/27.


look at it another way.


the number of possible choices is 3 * 3 * 3 = 27


only one of those choices will be the correct choice.


her probability of winning is therefore 1/27.