If X is a random variable with mean -3 and standard deviation 2, Y is a random variable with mean...
A random variable X is known to always be positive and have a standard deviation of 5 and E[x^2] = 125. Another random variable (Y) is known to have a mean twice as large as (X) and E[Y^2] = 500. Find the following: a.) E[X] b.) E[2X + 5] c.) Var(Y) d.) E[(Y-5)^2] e.) Assuming X and Y are independent find Var(2X - Y +5)
Given a random variable X, with standard deviation σx, and a random variable Y = a + bX, show that if b < 0, the correlation coefficient, pxy = -1, and if b > 0, pxy = 1. What is the correlation coefficient if a/b=π and a=(1+√2)/5 ?
Problem 2. Assume that random variable X has normal distribution with mean 2 and standard deviation of 5 (1) Find the density of random variable Y = X3. (2) Find the mean and variance of random variable Y defined above in (1)
Find the mean, variance and standard deviation for the random variable X: Random Variable X -2 1 3 P(X = x) 0.1 0.3 .6 Show the calculations that you need for each part. You will get no credit for using your calculator or Excel and only giving the answer. You should write out: mean = ........ (show how the mean is calculated) Vairance = .............. Standard Deviation = ................
Consider the following information about variable X: Mean = 4, standard deviation = 2. Consider the following information about variable Y: Mean = 5, standard deviation = 3. If there is a correlation of r = 0.52 between variable X and variable Y, what is the intercept for a simple linear regression equation predicting Y on the basis of X? Please provide your answer as a raw score (not a z score) with a minimum of two decimal places.
Let X be a random variable with mean 93 and standard deviation 13. If L = 3-2X what is the mean of L?
Assume the random variable x is normally distributed with mean y = 50 and standard deviation o=7. Find the indicated probability P(x > 40) P(x >40) - (Round to four decimal places as needed.) Assume the random variable x is normally distributed with mean = 88 and standard deviation o = 4. Find the indicated probability P(76<x<85) P(76<x<85)= (Round to four decimal places as needed.) Assume a member is selected at random from the population represented by the graph. Find...
Random variable X has mean Ux=24 and standard deviation σx =6. Randon variable Y has mean Uy =14 and standard deviation σY = 4. A new random variable Z was formed, where Z=X+Y. What can we conclude about X, Y, and Z with certainty? That is, which one is true?
3. Suppose we have a random variable X with mean a new random variable Y as = 7 and variance a4. We define Y 3 5X Find the standard deviation of Y
6.33 Let x be a continuous random variable that is normally distributed with a mean of 25 and a standard deviation of 6. Find the probability that x assumes a value a. between 28 and 34 b. between 20 and 35 6.34 Let x be a continuous random variable that has a normal distribution with a mean of 30 and a stan- dard deviation of 2. Find the probability that x assumes a value a. between 29 and 35 b....