Consider the two regression lines 3x+2y=26 and 6x+y=31,
(a) Find the mean value and correlation coefficient between x and y.
(b) If the variance of y is 4, find the S.D. of x.​

Answers

Answer 1

The regression lines 3x+2y=26 and 6x+y=31 are linear regressions

The mean values are 4 and 7 and the correlation coefficient between x and y is 0.25The standard deviation of x is 2/13

The mean value and the correlation

We have the equations to be:

3x+2y=26 and 6x+y=31

Make y the subject in the second equation

y = 31 - 6x

Substitute y = 31 - 6x in the first equation

3x+2[31 - 6x] = 26

Expand

3x+ 62 - 12x = 26

Collect like terms

3x - 12x = 26 - 62

Evaluate

-9x = -36

Divide by - 9

x = 4

Substitute x = 4 in y = 31 - 6x

y = 31 - 6 * 4

y = 7

This means that the mean values are 4 and 7

To determine the correlation coefficient, we make y the subject in 3x+2y=26 and x the subject in 6x+y=31.

So, we have:

y = 13 - 3x/2 and x = 31/6 - 1/6y

The above means that:

Bxy = -1/6 and Byx = -3/2

The correlation coefficient is then calculated as:

r^2 = Bxy * Byx

r = -1/6 * -3/2

r = 0.25

Hence, the correlation coefficient between x and y is 0.25

The standard deviation of x

We have:

Var(y) = 4

In (a), we have:

y = 13 - 3x/2

To solve further, we make use of:

Var(y) = Var(ax + b) = a^2Var(x)

This gives

Var(y) = Var(13 - 3x/2) = 13^2 * Var(x)

So, we have:

Var(y) = 13^2 * Var(x)

Substitute 4 for Var(y)

4 = 13^2 * Var(x)

Divide both sides by 13^2

4/13^2 = Var(x)

Express 4 as 2^2

(2/13)^2 = Var(x)

So, we have:

Var(x) = (2/13)^2

Take the square root of both sides

SD(x) = 2/13

Hence, the standard deviation of x is 2/13

Read more about regression lines at:

https://brainly.com/question/4341286


Related Questions

10) Complete the net worth statement by determining the total assets and total liabilities. What is the net worth? A) $178,000 B) $180,338 C) $1,052,662 D) $1,233,000

Answers

Answer:

C) $1,052,662

Step-by-step explanation:

Sorry the answer was late and also this is the right answer because i did the test

Solve for the unknown side and find perimeter of the figure below note that the figure is not drown to scale.​

Answers

Answer:

[tex]x = 12\ m,\ perimeter = 63\ m[/tex]

Step-by-step explanation:

Step 1:  Determine x

[tex]\frac{15\ m}{10\ m} = \frac{x}{8\ m}[/tex]

[tex](15\ m*8\ m) = (10\ m * x)[/tex]

[tex]120\ m^2 / 10\ m = x * 10\ m / 10\ m[/tex]

[tex]12\ m = x[/tex]

Step 2:  Determine the perimeter of the figure

[tex]18\ m + 15\ m + 10\ m + 8\ m + 12\ m[/tex]

[tex]63\ m[/tex]

Answer:  [tex]x = 12\ m,\ perimeter = 63\ m[/tex]

a farmer has 47 eggs.He packs 6 eggs in each box. How many egg boxes does he need to packall the eggs?​

Answers

We need to divide up 47 eggs into boxes of 6. Therefore, we are doing a division problem.

6 x 7 = 42

42 is as close as we can get to 47 without going over. So, at this point, we need 7 boxes.

BUT - There are 5 eggs left without a box. We cannot have part of a box either. Therefore, we need to add in another box.

7 + 1 = 8

He needs 8 boxes to pack all the eggs.

Hope this helps!

Answ

Step-by-step explanation:

17 boxes 47 divided by six so it is 17 boxes hope it helps:)

solve the following pair of equations by elimination method: x+y=4, 2x+y=3​

Answers

Answer:

x = 1

y = 5

Step-by-step explanation:

x + y = 4 __ (1)

2x + y = 3 __ (2)

equation (1) x 2, (2) x 1

2x + 2y = 8

2x + y = 3

0  + y = 5

y= 5 (ANS)

x + y = 4

x + 5 = 4

x = 5 - 4

x = 1 (ANS)

I HOPE MY ANSWER IS CORRECT IF NOT I APOLOGIZE.

Les gusta mi dibujo a mano con lapiz y papel

Answers

Está bonito, solo algunos detalles, pero con practica creeme que va estar mejor. Los dedos de las manos hay que trabajar más, ¡Está bonito!

integrate the following by parts |xcos x dx​

Answers

[tex]\displaystyle \int x \cos x ~dx\\\\=x\displaystyle \int \cos x ~dx- \displaystyle \int \left(\dfrac{d}{dx} x \displaystyle \int \cos x ~dx \right) dx\\\\=x\sin x - \displaystyle \int\left( \sin x \right) dx\\ \\=x \sin x - (-\cos x) +C\\\\=x \sin x + \cos x +C[/tex]

8 points
Find the measure of the arc or
angle indicated. Assume that
lines which appear tangent are
tangent. *
F
E
46°
?
?
570
D
с
T
O 123
O 149
O 167
O 93

Answers

que chingue a su madre la jimena.

Step-by-step explanation:

PLS HELPPPPPPPPP Jake is eating cereal he counts how much cereal he has. He has 78 and eats 56 how much does he have left.

Answers

Answer:

22

Step-by-step explanation:

78-56 5 goes in to 7 2 times so 2 is th tens diget  8-6=2 so the answer is 22

You roll a 6-sided die. What is P(divisor of 12)? Write your answer as a fraction or whole number.​

Answers

Answer:

[tex]\frac{5}{6}[/tex]

Step-by-step explanation:

The divisors of 12 that are ≤12 are 1, 2, 3, 4, and 6. The probability that the roll of a dice will be a divisor of 12 is 5/6.

Answer:

Step-by-step explanation:

5/6

Find sin(2x), cos(2x), and tan(2x) from the given information.
sin(x) = [tex]-\frac{3}{5}[/tex] for [tex]\frac{3\pi }{2}[/tex] < x < 2

Answers

I assume 3π/2 < x < 2π, so that x is in the 4th quadrant. For angles x terminating in Q4, we have sin(x) < 0 and cos(x) > 0, so tan(x) = sin(x)/cos(x) < 0.

This means that, using the Pythagorean identity,

cos(x) = + √(1 - sin²(x)) = 4/5

tan(x) = (-3/5) / (4/5) = -3/4

Recall the double angle identities:

sin(2x) = 2 sin(x) cos(x) = 2 (-3/5) (4/5) = -24/25

cos(2x) = 2 cos²(x) - 1 = 2 (4/5)² - 1 = 7/25

tan(2x) = 2 tan(x) / (1 - tan²(x)) = 2 (-3/4) / (1 - (-3/4)²) = -24/7

Pls help! ASAP [tex] [/tex]

Answers

Answer:

BC

Seg AC

Ray KM

Determine the lateral and total surface area
of the regular triangular pyramid.
15 cm
13 cm
Lateral Surface Area
Total Surface Area

Answers

The areas of the square pyramid are the amount of space on it

The lateral surface area is 292.5 square cmThe total surface area is 354.85 square cm

How to determine the lateral surface area?

The given parameters are:

Base (b) = 15 cm

Slant height (l) = 13 cm

The lateral surface area is calculated using:

L = 1.5bl

So, we have:

L = 1.5 * 15 * 13

Evaluate the product

L = 292.5

How to determine the total surface area?

This is calculated using:

T = L + 0.25√3b^2

So, we have:

T = 292.5 + 0.25√3 * 12^2

Evaluate

T = 354.85

Hence, the total surface area is 354.85 square cm

Read more about areas at:

https://brainly.com/question/24487155

Nolan drew a pre-image of a trapezoid using a dashed line. Which shows an isometric transformation of his pre-
image??

Answers

Answer:

C

Step-by-step explanation:

i just guessed but it was correct

What Is the area in a triangle 9m 11m?​

Answers

Answer:

49.5

Step-by-step explanation:

area of triangle = (b x h) / 2

9 x 11 = 99

99 / 2 = 49.5

Hope this helps!

- profparis

A farmer sells eggs in containers holding a dozen eggs. If he has 2178 eggs, how many containers will be filled completely? How many eggs will be left over?

Answers

Answer:

~181 containers filled completely, 6 eggs left over

Step-by-step explanation:

2178 ÷ 12 (a dozen, the number of eggs per container) = 181.5 containers

181 × 12 = 2,172 eggs

2,178 eggs - 2,172 = 6 eggs left over

if x+y = -10 and x-y = 2 what is the value of x

Answers

Answer:

  x = -4

Step-by-step explanation:

The solution to a "sum and difference" system of equations can be found by adding the equations together.

  (x +y) +(x -y) = (-10) +(2)

  2x = -8 . . . . . . simplify

  x = -4 . . . . . . . divide by 2

_____

Additional comment

 y = -6, though this question did not ask that value.

Use a graphing calculator to approximate the vertex of the graph of the parabola defined by the following equation. y = x squared + 2 x + 10 a. (1, 9) c. (1, 10) b. (-1, 10) d. (-1, 9)

Answers

Step-by-step explanation:

Answer: its d

Step-by-step explanation:

PLEASE HELP ILL GIVE THANKS, 5.0, AND BRAINLIEST TO WHOEVER ANSWERS CORRECTLY PLEASE HELP AND ILL GIVE A HIGH POINT COUNT
Sophie bikes at a
speed of s miles per hour. Her friend Rana is slower, her biking
speed 1S only r miles per hour.
Today the girls went for 20 miles trip, each girl was biking at her usual speed. How
long did Sophie wait for Rana after her own arrival to the finish?

Answers

Answer:

if Rama road  1 mph  Sophie waited  (20-4) = 16 hours

Step-by-step explanation:

Sophie road 5 mph for 20 miles

distance = rate of speed times time traveled

d = st

20 =5t

t = 20/5 = 4 hours

Rana road r mph for 20 mile

d=rt

20=rt

t =20/r

Sophie waited  20/r - 4  hours

20/r -4 =  (20-4r)/r

if Rana road at   4 mph,  Sophie waited (20-4(4))/r =  4/4 = 1 hour

If Rana road at  3 mph,  Sophie waited (20-4(3))/3 = 8/3 = 2 hours 40 minutes

if Rama road at 2 mph  Sophie waited (20-4(2))/2 = 12/2 = 6 hours

if Rama road  1 mph  Sophie waited  (20-4) = 16 hours

Questione Simplify Cosa + 2Cos(a +240")​

Answers

Step-by-step explanation:

[tex] \cos(a) + 2 \cos(a + 240) [/tex]

[tex] \cos(a) + 2 \cos(a) \cos(240) - \sin(a) \sin(240) [/tex]

[tex] \cos(a) + 2( - \frac{ \cos(a) }{2} + \frac{ \sqrt{3} }{2} \sin(a) )[/tex]

[tex] \cos(a) - \cos(a) + \sqrt{3} \sin(a) [/tex]

[tex] \sqrt{3} \sin(a) [/tex]

If you graph the new identity, and the og identiy, they will be conciding graphs, so they are the same identity.

which number doesn't belong?
21, 18, 16, 7, 6
18, 10, 13, 11, 16
2, 16, 9, 7, 17
11, 16, 4, 8, 2
6, 9, 11, 15, 18
19, 9, 14, 8, 11

Answers

Answer:

21

Step-by-step explanation:

Most of the numbers are within the same range. Then you have 21 which is slightly out of range from the next highest 19.

Betty has some bottles.
4
7
of the bottles are big and
4
5
of the remaining bottles are small. The rest of the bottles are tiny.
What fraction of the bottles are tiny?

Answers

I hope it is useful for you:)

In a recent poll, 50 teenagers were asked do they exercise regularly. 35% of them said they do exercise regularly? What is the random Variable?

Answers

Step-by-step explanation:

In a recent poll, 50 teenagers were asked do they exercise regularly. 35% of them said they do exercise regularly? What is the random Variable?

the length of a rectangle is 10 cm and its width is 2 cm less than 1/2 of its length. find the area of the rectangle​

Answers

Answer:

A=wl=3·10=30

A=30

Step-by-step explanation:

mean of 39,82,74,96,64,52,74

Answers

Mean
=(39+82+74+96+64+52+74)/7
=481/7
= 68.71

4
Which equation does not have a solution?
A. -3d + 7 = -9
B. 8d + 7 = -4(-2d - 4)
C. 54+ 15 = 15
D. 2(d' + 6) = -2d - 12

Answers

Answer:

Option B

Step-by-step explanation:

A.)

-3d + 7 = -9

➝ -3d = -7 - 9

➝ -3d = -16

➝ d = -16/-3

➝ d = 16/3

Solution is d = 16/3

B.)

8d + 7 = -4(-2d - 4)

➝ 8d + 7 = 8d + 16

➝ 8d - 8d = 16 - 7

➝ 0 = 9

It has no solution.

C.)

➝ 5d + 15 = 15

➝ 5d = 15 - 15

➝ 5d = 0

➝ d = 5/0

➝ d = 0

Solution is d = 0

D.)

➝ 2(d + 6) = -2d - 12

➝ 2d + 12 = -2d -12

➝ 2d + 2d = -12 -12

➝ 4d = 24

➝ d = 24/4

➝ d = 6

Solution is d = 6

Hence,

(Option B) 8d + 7 = -4(-2d - 4) has no solution.

Mr. Turner has two Algebra 1 classes. With one class, he lectured and the students took notes. In the other class, the students worked in small groups to solve math problems. After the first test, Mr. Turner recorded the student grades to determine if his different styles of teaching might have impacted student learning.

Class 1: 80, 81, 81, 75, 70, 72, 74, 76, 77, 77, 77, 79, 84, 88, 90, 86, 80, 80, 78, 82

Class 2: 70, 90, 88, 89, 86, 86, 86, 86, 84, 82, 77, 79, 84, 84, 84, 86, 87, 88, 88, 88

1. Analyze his student grades by filling in the table below. Which class do you think was the lecture and which was the
small group? Why?

Answers

                          Q1            Q2       IQR   Mean      Median         MAD

Class 1            76.25         81.75    5.5      79.35         79.50       3.12

Class 2             84             88        4           84.60         86           3.85

What is Q1, Q3, IQR, Mean, Median and the MAD?

The first step is to arrange the grades in the classes in ascending order.

Class 1: 70, 72, 74, 75, 76, 77, 77,77, 78, 79, 80, 80, 80, 81, 81, 82, 84, 86, 88, 90

Class 2: 70, 77, 79, 82, 84, 84, 84, 84, 86, 86, 86, 86, 86, 87, 88, 88, 88, 88, 89, 90

Q1 for class 1= 1/4(n + 1) = 21/4 = 5.25 = 76.25

Q2 for class 2 = 1/4(n + 1) = 5.25 = 84

Q3 for class 1= 3/4(n + 1) = 15.75 = 81.75

Q3 for class 2 = 3/4(n + 1) = 15.75 = 88

IQR for class 1 = Q3 - Q1 = 81.75 - 76.25 = 5.50

IQR for class 2 = Q3 - Q1 = 88 - 84 = 4

Mean for class 1 = sum of grades / total number of grades = 1587 / 20 = 79.35

Mean for class 2 = sum of grades / total number of grades= 1692 / 20 = 84.6

Median for class 1 = (n + 1) / 2 = 21/2 = 10.5 = 79.50

Median for class 1 = (n + 1) / 2 = 21/2 = 10.5 = 86

MAD = [tex]\frac{1}{n}[/tex]∑ l x - m(x) l

Where: n = number of observations

x = number in the data set

m = mean

Mean absolute deviation for class 1 = 62. 3/ 20 = 3.12

Mean absolute deviation for class 2. = 77/ 20 = 3.85

To learn more about median, please check: https://brainly.com/question/20434777

The difference between the supplement of an angle and twice its complement is 28°, find the measure of the supplement of the angle.​

Answers

Answer:

152°

Step-by-step explanation:

Supplementary angles are two angles that sum to 180°

Complementary angles are two angles that sum to 90°

Let x° = the angle

⇒ Supplement of the angle = 180° - x°

⇒ Complement of the angle = 90° - x°

The difference between the supplement of an angle and twice its complement is 28°:

⇒ (180 - x)°  - 2(90 - x)° = 28°

⇒ 180 °- x° - 180° + 2x° = 28°

⇒ x = 28°

Therefore, the measure of the supplement of 28° is:

180° - 28° = 152°

Find each difference vertically.
3. (2x ^2 – 2x ^4) — (x4 – x2)

Answers

Answer:

answer: -2x^4 +2x^2-2x

Helpppppppppppppppp
find x​

Answers

Answer:

Answer is √2+11/2

And you can use calculator to get even more accurate answer though...

Step-by-step explanation:

this is what i get i hope this will hepl you ♡

answer for this question. Thank you!

Answers

I am so confused right now
Other Questions
(4x - 3)Find the value of 'x'.(2x + 9)A. 53B. 14C. 16D. 37 Why does the author include the anecdote about the McCoy family in this section? The cost to mail a package is $8 for the first 4 pounds and 25 cents for each additional ounce. Which of the following functions represents the cost to mail a package if x is the number of ounces over 4 pounds?f( x) = 32 + 0.25 xf( x) = 0.25( x + 4)f( x) = 0.25+ 8 xf( x) = 8 + 0.25 x 2. Viscosity is a measure of how easily a fluid flow such as water. Thabo wants to investigate how viscosity of water varies with temperature which can be determined by the following correlation: u=c10 where u = viscosity (N/s. m) T = temperature (K) C1 = 2.414 x 10-(N/s. m) C2 = 247.8 K C3 = 140 K Using MATLAB, create a table for Thabo that shows the viscosity of water as a function of temperature in the range of 0 C (273.15 K) to 100 C (373.15 K) in increments of 5 C. Also, create a graph showing the value of viscosity as a function of temperature. [10 marks] __________ is the application of modern measurement technologies and contemporary organizational design to understand, quantify, and optimize marketing spending. please help i need help DescribingWrite two sentences about the town of Makkah compare the effect of the ozone in the troposphere with its effect in the stratosphere where is it harmful where is it helpful Choose all that apply for Grasslands Select 3 correct answer(s)Question 2 options:Contains grasses and woody plants occur in all climatic zonesrainfall is low no trees and shrubs Based on the passage, what conclusion can be made about Tans opinion of language ability tests?She believes they are an imperfect way of understanding a persons expression.She believes they are essential to determining who needs extra instruction.She believes they are often filled with interesting stories for students.She believes they are a good way of getting students to think imaginatively. factor each completelyn^2 - 11n + 10 explain any four effects caused due to exercise use chemical of chemical feritilizer on environment Which rebuttal did the affirmative present in response to the negatives claim and evidence? the negative stated that universities could not provide the same quality of education if they were funded by the state. if higher education were free for all, colleges would need to spend significantly less money on recruiting new students. state funding could be dedicated to supporting education and maintaining the success of students in higher education. Simplify: 4y + 3 +9y+ 6O 13y + 9O 22yO 7y + 15O 22 h(t)=50 5th, left parenthesis, t, right parenthesis, equals, 50, minus, start fraction, t, divided by, 5, end fractionh(35)=h(35)= Why was the ANC created? Bella baked a two layer cake.The bottom layer has dimensions of 4 inch x 6inch x 8inch.The dimensions of the top layer are half bottom.What is the volume of the top layer. PLS HELP 1.Seats in a theater are curved from the front row to the back. The front row has 18 chairs, the second has 26and the third has 34, and so on.a.Write a recursive rule for this series (2 points):b. Write an explicit rule in simplified form for this series:Show the steps to simplify. (2 points)c. Using the explicit formula, find the number of chairs in row 7 (show work) (3 points):on Voy bob ochotebu ma'istod. The auditorium can hold 12 rows of chairs. Write a sigma notation for this series, and then use either seriesformulas to calculate how many chairs can fit in the auditorium. Show all work. (5 points) Please explain someone!!! [4+3]2071 Q. No. 14 (0)State Bolazano Weirstrass theorem. If A is any set in R then prove A = AUA'. [1+3]2071 Q. No. 14 (ii) aDefine isolated point.And find the isolated point for the set A = (0, 1){2}.2072 Q. No. 2