Number and Algebra
Functions
Geometry & Trigonometry
Statistics & Probability
Calculus
Given E(X)=5E(X)=5E(X)=5, E(Y)=−1E(Y)=-1E(Y)=−1, and Cov(X,Y)=2\text{Cov}(X,Y)=2Cov(X,Y)=2, find E(XY)E(XY)E(XY).
Given Var(X)=4\text{Var}(X)=4Var(X)=4, find the standard deviation of 0.5X0.5X0.5X.
Given E(X)=1E(X)=1E(X)=1 and E(Y)=2E(Y)=2E(Y)=2, find E(4X−5Y+3)E(4X - 5Y + 3)E(4X−5Y+3).
Given E(X)=−3\text{E}(X)=-3E(X)=−3 and Var(X)=2\text{Var}(X)=2Var(X)=2, find Var(X+5)\text{Var}(X + 5)Var(X+5).
Given E(X)=0.7E(X)=0.7E(X)=0.7 and E(X2)=0.9E(X^2)=0.9E(X2)=0.9, find Var(2X)\text{Var}(2X)Var(2X).
Given Var(X)=6\text{Var}(X)=6Var(X)=6, Var(Y)=9\text{Var}(Y)=9Var(Y)=9 and Cov(X,Y)=5\text{Cov}(X,Y)=5Cov(X,Y)=5, find Cov(2X−Y,3X+4Y)\text{Cov}(2X - Y, 3X + 4Y)Cov(2X−Y,3X+4Y).
Given Var(X)=9\text{Var}(X)=9Var(X)=9, Var(Y)=16\text{Var}(Y)=16Var(Y)=16, and Cov(X,Y)=6\text{Cov}(X,Y)=6Cov(X,Y)=6, find Var(2X−3Y)\text{Var}(2X - 3Y)Var(2X−3Y).
Given E(X)=0\operatorname{E}(X)=0E(X)=0 and Var(X)=1\operatorname{Var}(X)=1Var(X)=1, find Var(X+23)\operatorname{Var}\left(\frac{X+2}{3}\right)Var(3X+2).
Given E(X)=2E(X)=2E(X)=2 and Var(X)=3\text{Var}(X)=3Var(X)=3, find E(X2)E(X^2)E(X2).
Given E(X)=5E(X)=5E(X)=5, find E(3X−2)E(3X - 2)E(3X−2).
Given Var(X)=9\text{Var}(X)=9Var(X)=9, Var(Y)=16\text{Var}(Y)=16Var(Y)=16, and Cov(X,Y)=6\text{Cov}(X,Y)=6Cov(X,Y)=6, find Var(X+Y)\text{Var}(X+Y)Var(X+Y).
Given Var(X)=4\text{Var}(X)=4Var(X)=4, find Var(3X+1)\text{Var}(3X + 1)Var(3X+1).
Previous
Question Type 7: Finding the variance for a given continuous distribution and PDF
Next
No next topic