10. If x1, x2 and x3 are three variates measured from their respective means as origin and of equal variances, find the coefficient of correlation between (x1 + x2) and (x2 + x3) in terms of r12, r13 and r23 and show that it is equal to

Q: A sample of 7070 women is​ obtained, and their heights​ (in inches) and pulse rates​ (in beats per​…

A: It is given that the correlation coefficient (r) is 0.221.

Q: . A sample of 60 women found that they run an average a  of 5km a week with a variance of 64.…

A: Given Data : For Sample 1 x̄1 = 5 s1 = 8 n1 = 60 For Sample 2 x̄2 = 3 s2…

Q: Two lines of regression are given by 5x+7y-22=0 and 6x+2y-22=0. If the variance of y is 15, find the…

A: Given: 5x+7y-22=0 6x+2y-22=0 V(y) = σx2= 15 Now, the regression equation y on x is, y = -3x + 11  x…

Q: Consider the variable X whose mean and variance are given respectively by Hx = 27.2 and Var(X) =8.…

A: GivenμX=27.2Var(X)=8

Q: A firm purchases two types of industrial chemicals. Type I chemical costs $3 per gallon, whereas…

A:

Q: If X, Y and Z are uncorrelated and independent variables with the same variance o and zero mean.…

A:

Q: 40. Two regression lines of a sample are X+6Y=6 and 3X+2Y 0. Find the correlation coefficient.

A:

Q: The regression lines between two random variables X and Y is given by 3X + Y = 10 and3X + 4Y = 12…

A:

Q: Noise pollution is measured in decibels. In Nevada any motorcycle made after 1980 may not be any…

A: The null and the alternative hypotheses are, Test statistic: Thus, the test statistic is 58.

Q: There are two risky shares, where you have calculated the means, and the correlation coefficient of…

A: There are two risky shares, where you have calculated the means, and the correlation coefficient of…

Q: Two variables have the regression lines 3x + 2y = 26 and 6x + y = 31. Find the mean values, the…

A:

Q: NGmiS5. The line of regression of marks in Statistics (X) on marks in Accountancy (Y) for a class of…

A:

Q: Show that if X₁ and X₂ are standard normal variate with correlation cofficient p between them, then…

A:

Q: A researcher wanted to compare that activity of pet dogs living in the city and pet dogs living in…

A: A t-test is a type of inferential statistic used to determine if there is a significant difference…

Q: If the variance of the sum is Var(X+Y) = 6 and Var(X) = Var(Y) = 4, then what is the correlation…

A: given data  Var(X+Y) = 6 Var(X) = Var(Y) = 4 corr(X,Y) = ?

Q: In the two regression lines are 3y + 9x = 46 and 3x + 12y = 19, determine which one of %3D these is…

A:

Q: A medical researcher wishes to see whether the variance of the heart rates (in beats per minute) of…

A: The null and alternative hypotheses are given below. H0: σ12 = σ22 H1: σ12 ≠ σ22 The test statistic…

Q: Suppose a car's city miles per gallon rating can be determined by the car's weight. The means and…

A: In this case, the city MPG is the dependent variable (y) and weight is the independent variable (x).

Q: 6. There is a class of 80 students taking Maths and English lectures; the regression equation of…

A: y = a + bx  where b = slope

Q: The cholesterol levels of adult males are approximately normally distributed with a mean of 224…

A: State the hypotheses That is, there is no evidence that the variance of the cholesterol levels of…

Q: Two regression lines of a sample are X+6 Y=6 and 3X+2Y=0. Find the correlation coefficient.

A:

Q: Two students sit for a university final exam whose scores are known to be normally distributed. The…

A: If raw scores are given by X= 63, Y= 93 Then z score for x is given by, Z= (X- mu)/sigma Where mu is…

Q: The cost of a week long vacation in a city has a mean of 1000 and a variance of 1200. The city…

A: Solution:  Given information: μ= 1000  Population mean σ2= 1200  Population varaince tax = 10%

Q: A least squares line is given by =  3 + (-2)*x. You  are told that the sample variance of x is 25…

A: Given regression equation is y=3-2x Sample variance of x is 25 Sample variance of y is 144 Here,…

Q: Correlation Coefficient Mean SD Weight (pounds) 3185.5 494.5 -907 City MPG 20.962 3.165

A:

Q: The mean age of children at the X College daycare center is 6. The ages are skewed in a negative…

A: μ=6 σ2= 5.1

Q: A correlation of +.20 means that [blank] of the variance in the outcome variable is accounted for by…

A: Solution: From the given information, r=0.20.

Q: Find the variance

A: Given : X~N(0, 7)

Q: Suppose the scatter diagram of a random sample of data pairs (x,y) shows no linear relationship…

A: If the value of the sample correlation coefficient is 1, then there is strong positive linear…

Q: Is there enough evidence to question Harley’s claim of 10 decibels?

A: Given: Sample size (n) = 30 Sample variance (s2) = 20 Hypothesized variance (σ2) = 10

Q: A sample of 70mwomen is​ obtained, and their heights​ (in inches) and pulse rates​ (in beats per​…

A: Solution: From the given information, the equation of the regression line is

Q: The sample correlation coefficient is equal to the covariance of x and y divided by the square root…

A: It is an important part of statistics . It is widely used .

Q: Suppose Y1, Y2 and 3Y are not correlated variables, however, have the same standard deviation. Show…

A: Given  Y1 , Y2, Y3 are independent of each other.  They have same standard deviations

Q: If covariance between X and Y variables is 10 and the variances of X and Y are respectively 16 and…

A: The objective is to find correlation coefficient

Q: You are conducting a study to see if students do better when they study all at once or in intervals.…

A: 1. Computing the values of the test statistics: The null and alternative hypotheses are: It is…