Respostas

2013-07-02T20:41:17-03:00

K = cara
C = coroa

{(k,k,k), (k,k,c), (k,c,k), (c,k,k), (k,c,c), (c,k,c),(c,c,k),(c,c,c)}

 

Os 4 primeiros eventos atendem, 4/8 = 1/2.

 

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OU

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Pr(X=1) + P(X=0) = Comb(3,1)(1/2)^1(1/2)^2 + Comb(3,0)(1/2)^3(1/2)^0 = 3/8+1/8 = 4/8

1 2 1