If X denotes the number on the upper face of a cubical die when it is thrown, find the mean of X
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The sample space of the experiment consist of 6 elementary events where, xi=1, 2, 3,4,5,6
The random variable X i.e. number on the upper face of a cubical die when it is thrown is-1,2,3,4,5,6
P(X=1) =P (1) =![]()
P(X=2) =P (2) =![]()
P(X=3) =P (3) =![]()
P(X=4) =P (4) =![]()
P(X=5) =P (5) =![]()
P(X=6) =P (6) =![]()
The probability distribution of X is


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E(X) = 3.5