Could someone help please?

koko1234

New member
In the amusement park there are three small carousels that work with coins of 1 each. One never works, another always works, while the third works 1/2 of the times. As I walk, I think of them and want to determine who is the one who always works to take my sister to her some day. There is no one there and I have exactly three coins of one 1 each. I try one carousel and it doesn't work. I try another twice and it works both times. What is the probability that the second one I tried was the most reliable?

Subhotosh Khan

Super Moderator
Staff member
In the amusement park there are three small carousels that work with coins of 1 each. One never works, another always works, while the third works 1/2 of the times. As I walk, I think of them and want to determine who is the one who always works to take my sister to her some day. There is no one there and I have exactly three coins of one 1 each. I try one carousel and it doesn't work. I try another twice and it works both times. What is the probability that the second one I tried was the most reliable?
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