247. Random variables X and Y have joint distribution X=0 1/15 X=1 Y=0 a X=2 2/15 Y=1 a b a Y=2 2/15 a 1/15 Let a be the value that minimizes the variance of X. Calculate the variance of Y. (A) 2/5 (B) 8/15 (C) 16/25 (D) 2/3 (E) 7/10
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So, we have: $$1/15 + a + 2/15 + a + b + a + 2/15 + a + 1/15 = 1$$ $$4a + b = 8/15$$ Show more…
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