We have
E[X] = 4
E[Y] = -2
We need to find E [5X - 3Y]
By linearity property of expectation we have,
E[X+Y] = E[X] + E[Y]
also if c is constant
E[cX] = c.E[X]
Hence,
E [5X - 3Y] = E[5X] - E[3Y]
= 5*E[X] - 3*E[Y]
= 5*4 - 3*(-2)
= 20 + 6
= 26
Let X and Y be random variables with the follow E(Y) μ,--2 Var(x) o, 0.3 Var(Y)-σ,-0.5...
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