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15 votes
15 votes
I don't understand this question​

I don't understand this question​-example-1
User Andy Braham
by
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1 Answer

21 votes
21 votes

The probabilities of all possible outcomes must sum to 1. So the missing probability is

1 - 1/2 - 3/10 - 1/20 = (20 - 10 - 6 - 1)/20 = 3/20

User Dmitriy Zapevalov
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