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Solve the following problem :
Following is the probability distribution of a r.v.X.
x  – 3  – 2  –1  0  1  2  3 
P(X = x)  0.05  0.1  0.15  0.20  0.25  0.15  0.1 
Find the probability that X is even.
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Solution
P(X is even)
= P(X = –2 or X = 0 or X = 2)
= P(X = 2) + P(X = 0) + P(X = 2)
= 0.10 + 0.20 + 0.15 = 0.45
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