In: Statistics and Probability
Suppose that X1 and X2 are two random variables. Suppose that X1 has mean 1 and variance 4 while X2 has mean 3 and variance 9. Finally, suppose that the correlation between X1 and X2 is 3/8. Denote Y = 2X1 − X2. (67) The mean of Y is (a) 1 (b) 4 (c) -2 (d) -1 (68) The variance of Y is (a) 25 (b) 4 (c) 9 (d) 16 (69) The standard deviation of Y is (a) 5 (b) 2 (c) 3 (d) 4 (70) The correlation between X1 and Y is (a) 0 (b) 23/32 (c) 16/9 (d) 1 i need a clear, thorough answer to question 70 please.