Show that Cov(X, Y 1 Z) 5 Cov(X, Y) 1 Cov(X, Z). b. Let X1 and X2 be quantitative and verbal scores on one aptitude exam, and let Y1 and Y2 be corresponding scores on another exam. If Cov(X1, Y1) 5 5, Cov(X1, Y2) 5 1, Cov(X2, Y1) 5 2, and Cov(X2, Y2) 5 8, what is the covariance between the two total scores X1 1 X2 and Y1 1 Y2

Kayla and alberto are selling fruit for a school fundraiser. customers can buy small boxes of grapefruit and large boxes of grapefruit. kayla sold 3 small boxes of grapefruit and 1 large box of grapefruit for a total of $65. alberto sold 1 small box of grapefruit and 1 large box of grapefruit for a total of $55. what is the cost each of one small box of grapefruit and one large box of grapefruit?