E[Y] in fXY(x, y) =X + 2Y; X = 0, 1140; otherwise

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E[Y] in
f_XY(x, y) = X + 2Y ; X = 0, 1
14
0; otherwise

1. 11
  7
2. 9
  14
3. 13
  14
4. 23
  14

Correct Option: D

	_∞	_∞
E[y] =			y.f _XY(x, y)
	^{X = – ∞}	^{Y = – ∞}

	₁	₂
E[y] =			(X + 2Y)
	^{X = 0}	^{Y = 1}	14

	₂
=		[Y(0 + 2Y) + Y(1 + 2Y)]
	^{Y = 1}	14

or E(y) =	1.2.1.(1 + 2.1) + 2.2.2 + 2(1 + 2.2.)
	14

E(y) =	2 + 3 + 8 + 10
	14

=	23
	14