Question 2
Here as we know that
E[aX + bY] = a E[X] + b E[Y]
V[aX + bY] = a2V[x] + b2V[Y]
V[aX - bY] = a2V[x] + b2V[Y]
(a) E[X -2] = E[X] - 2 = -2
(b) V[X - Y] = V[X] + V[Y] = = 3
(c) V[2X + 3Y] = 22V[X] + 32 V[Y] = 4 + 9 * 2 = 22
(d) V[X - 3Y - 5] = V[X] + 32 V[Y] = + 9 * 2 = 19
2. Let us assume that the population X has the mean μ and the variance σ2...
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