Sat Ii Math Level 2 Test 04 Solution 1 If F Is A Linear Function And F 3 7 F 5 1 And F X 11 2 What Is The Value Of X A 3 2 B Ppt Download
Cov(X Y,X 12Y) = 22E(XY)08−1608 = 22E(XY)−7172 To complete the calculation, it remains to find E(XY) To this end we make use of the still unused relation Var(X Y) = 8 8 = Var(X Y) = E((X Y)2)−(E(X Y))2 = E(X2)2E(XY)E(Y2)−(E(X)E(Y))2 = 2742E(XY)514−(57)2 = 2E(XY)−652, so E(XY) = 366 Substituting this, the numerator is 3, and the denominator is 8 A more illustrative example could involve a pie with 8 slices 1 of those 8 slices would constitute the numerator of a fraction, while the total of 8 slices that comprises the whole pie would be the denominator If a person were to eat 3 slices, the remaining fraction of the pie would therefore be