A study conducted by a TV station showed the number of televisions per household and the corresponding probabilities for ecach. Find the mean, variance, and standard deviation.
(in table)
Number of televisions
1 2 3 4
Probability P(X)
0.32 0.51 0.12 0.05
If you were talking a survey on the programs that were watched on television, how many program diaries would you send to ecach household in the survey?
1 answer
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