A team of researchers wants to determine whether pet owners are generally more satisfied with their lives than non-pet owners. To test their theory, the researchers randomly select 500 pet owners and 500 non-pet owners from several major metropolitan areas in the country. The researchers then interview the individuals, asking them a series of questions. Each response is assessed with a point value that is later translated to a satisfaction indicator. Of the pet owners surveyed, 380 of the 500 were found to be satisfied with their lives, while 336 of the 500 non-pet owners were found to be satisfied.
Would this study be considered an experiment or an observational study?

Answer:

1

Step-by-step explanation:

Computing Tv(X, X + a ) for any a∈(0,1)

Given that :  X∼Ber(0.5)

∴ The probability mass function

    P(X = 1 ) = 0.5

    P(X = 0) = ( 1 - 0.5 )

and expectation  E[X] = 0.5

hence ; TV ( X, X + a ) = 1

Answer:

x² + 3x - 10 = 0

x² - 25 = 0

Answer:

i guess its 1...

Step-by-step explanation:

Answer:

79 numbers

Step-by-step explanation:

39 x 39 = 1521 ( Find the square of 39)

40 x 40 = 1600 (Find the square of 40)

1600 - 1521 = 79 ( Finding the difference of the two squares)

Answer:

Hi im not got with graphs

Step-by-step explanation:

Answer:

x=-2, y=3

Step-by-step explanation:

make it easy first, solve for x in the second equation: x= -5+y.

then sub that in for the other x: 2(-5+y)+y= -1

now combine like terms: -10+3y= -1

solve for y: 3y=9, y= 3

then replace y for your second equation: x-3= -5

solve for x= -5+3.... so then its -2

check by replacing all variables with your new solutions:

2(-2), which is -4+3 does equal -1

(-2) -3 does equal -5.

your answers are x=-2, y=3

Answer is

5 gives the range of possible values for x.

Answer: 1547 bricks are required to build the staircase.

Step-by-step explanation:

We are given:

Number of bricks in the first step, [tex]a_1[/tex] = 131

Number of bricks in the second step, [tex]a_2[/tex] = 131 - 5 = 126

Number of bricks in the third step, [tex]a_3[/tex] = 126 - 5 = 121

Sequence become:

131, 126, 121, .....

These are in arithmetic progression where a = 131 and d (common difference) = -5

To calculate the sum of an AP, we use the formula:

[tex]S_n=\frac{n}{2}[2a+(n-1)d][/tex]

where,

n = number of terms = 17

Putting values in above equation, we get:

[tex]S_n=\frac{17}{2}[2(131)+(17-1)(-5)]\\\\S_n=\frac{17\times 182}{2}=1547[/tex]

Hence, 1547 bricks are required to build the staircase.

Answer:

A is is correct since the interquatile or a is 15 since 15 plus 15 equals 30 and 20 plus 20 equals 40

B is incorrect since the interquare are not both 30

C is incorrect since both interquatiles are wrong

D is incorrect since the standrard devations are off

Answer:

The equation of the new function is [tex]g(x) = \frac{x}{3}[/tex]

Step-by-step explanation:

Horizontally stretching a function:

Horizontally stretching a function f(x), by a factor of a, means that:

[tex]g(x) = f(\frac{x}{a})[/tex]

In this question:

[tex]f(x) = x[/tex], horizontally stretched by a factor of 3, so [tex]a = 3[/tex], and:

[tex]g(x) = f(\frac{x}{3}) = \frac{x}{3}[/tex]

The equation of the new function is [tex]g(x) = \frac{x}{3}[/tex]

Answer:

x = 5 or x = - 2

Step-by-step explanation:

Using the rules of logarithms

log x + log y = log (xy)

log x = log y ⇒ x = y

Given

ln(x- 3) + ln(x + 1) = ln(x + 7) , then

ln (x - 3)(x + 1) = ln (x + 7) , so

(x - 3)(x + 1) = x + 7 ← expand left side using FOIL

x² - 2x - 3 = x + 7 ( subtract x + 7 from both sides )

x² - 3x - 10 = 0 ← in standard form

(x - 5)(x + 2) = 0 ← in factored form

Equate each factor to zero and solve for x

x - 5 = 0 ⇒ x = 5

x + 2 = 0 ⇒ x = - 2

Answer:

The angle between the liens is 135 degree.

Step-by-step explanation:

Equation of first line

2 x + 5 y = 4 ...... (1)

Equation of second line

7 x + 3 y = 8 ..... (2)

The slope of a line is given by

[tex]m = \frac{- coefficient of x}{coefficient of y}[/tex]

Slope of first line

[tex]m = -\frac {2}{5}[/tex]

Slope of second line

[tex]m'= - \frac{7}{3}[/tex]

The angle between the two lines is given by

[tex]tan\theta = \frac{m- m'}{1 + m m'}\\\\tan\theta = \frac{-\frac{2}{5}+\frac{7}{3}}{1+\frac{2}{5}\times \frac{7}{3}}\\\\tan\theta = -1 \\\\\theta = 135^o[/tex]

Answer:

Step-by-step explanation:

=====================================================

Explanation:

The interior angles are consecutive numbers such as 1,2,3,... or 7,8,9... and so on. The gap between any two adjacent neighbors is 1.

For any polygon with n sides, the interior angles add up to 180(n-2)

We have n = 8 sides so the interior angles sum to 180(n-2) = 180(8-2) = 1080 degrees.

Any octagon has its interior angles add up to 1080 degrees.

-----------------------------

Let x be the smallest angle. The next angle up is x+1. After that is x+2 and so on until we reach x+7 as the 8th angle.

Add up those 8 angles, set the sum equal to 1080 and solve for x

x+(x+1)+(x+2)+(x+3)+(x+4)+(x+5)+(x+6)+(x+7) = 1080

8x+28 = 1080

8x = 1080-28

8x = 1052

x = 1052/8

x = 131.5

This is the smallest angle. The next angle up or the second smallest angle is x+1 = 131.5+1 = 132.5 degrees  (choice C)

Answer:

(a)

Mean

[tex]\bar x_1 = 31.375[/tex]

[tex]\bar x_2 = 41.75[/tex]

[tex]\bar x_3 = 53.00[/tex]

Standard deviation

[tex]\sigma_1 = 8.73[/tex]

[tex]\sigma_2 = 7.65[/tex]

[tex]\sigma_3 = 6.04[/tex]

(b) Yes, there is a difference in the mean

Step-by-step explanation:

Solving (a): The mean and standard deviation of each commercial

This is calculated as:

[tex]\bar x = \frac{\sum x}{n}[/tex]

For clothes:

[tex]\bar x_1 = \frac{43+24+42+35+28+31+17+31}{8}[/tex]

[tex]\bar x_1 = \frac{251}{8}[/tex]

[tex]\bar x_1 = 31.375[/tex]

For food:

[tex]\bar x_2 = \frac{30+38+46+54+47+42+34+43}{8}[/tex]

[tex]\bar x_2 = \frac{334}{8}[/tex]

[tex]\bar x_2 = 41.75[/tex]

For toys:

[tex]\bar x_3 = \frac{52+58+43+49+63+53+48+58}{8}[/tex]

[tex]\bar x_3 = \frac{424}{8}[/tex]

[tex]\bar x_3 = 53.00[/tex]

The sample standard deviation is:

[tex]\sigma = \sqrt{\frac{\sum(x - \bar x)^2}{n-1}}[/tex]

For clothes:

[tex]\sigma_1 = \sqrt{\frac{(43 - 31.375)^2 +.............+(31 - 31.375)^2}{8-1}}[/tex]

[tex]\sigma_1 = \sqrt{\frac{533.875}{7}[/tex]

[tex]\sigma_1 = \sqrt{76.2678571429}[/tex]

[tex]\sigma_1 = 8.73[/tex]

For food:

[tex]\sigma_2 = \sqrt{\frac{(30 - 41.75)^2 +............+(43 - 41.75)^2}{8-1}}[/tex]

[tex]\sigma_2 = \sqrt{\frac{409.5}{7}}[/tex]

[tex]\sigma_2 = \sqrt{58.5}[/tex]

[tex]\sigma_2 = 7.65[/tex]

For toys:

[tex]\sigma_3 = \sqrt{\frac{(52-53.00)^2+...................+(58-53.00)^2}{8}}[/tex]

[tex]\sigma_3 = \sqrt{\frac{292}{8}}[/tex]

[tex]\sigma_3 = \sqrt{36.5}[/tex]

[tex]\sigma_3 = 6.04[/tex]

Solving (b): Difference in mean in the commercials;

In (a), we have:

[tex]\bar x_1 = 31.375[/tex]

[tex]\bar x_2 = 41.75[/tex]

[tex]\bar x_3 = 53.00[/tex]

[tex]\bar x_1 \ne \bar x_2 \ne \bar x_3[/tex]

Hence, there is a difference in their means

Answer:

21 times 660 and then you will get the answer

Answer:

A) Independent

B) Dependent

Step-by-step explanation:

A) If we take a marble out and put the marble back, it means we have restored the sample to what it was initially and thus it doesn't affect probability of making another selection.

Thus, this is an independent event.

B) A card is taken from a deck of cards without replacement and set aside. Then after that another card is taken from the first sample, this means that the first sample size has now reduced and thus the first card taken affects the probability of the second card to be picked. Thus, this is a dependent event.

Answer:

D

Step-by-step explanation:

Plug in the numbers for the x-value and solve the equation.

| 3(80/3)/4 + 1 | = 16

| 3(-40/3)/4 + 1 | = 16

Answer:

[tex]x(x+y)^2[/tex]

Step-by-step explanation:

We are given that

[tex]x^3y+2x^2y^2+xy^3[/tex] and [tex]2x^3+4x^2y+2xy^2[/tex]

We have to find HCF.

[tex]x^3y+2x^2y^2+xy^3=xy(x^2+2xy+y^2)[/tex]

=[tex]xy(x+y)^2[/tex]

By using the formula

[tex](x+y)^2=x^2+2xy+y^2[/tex]

[tex]xy(x+y)^2=x\times y\times (x+y)^2[/tex]

[tex]2x^3+4x^2y+2xy^2=2x(x^2+2xy+y^2)[/tex]

[tex]=2x(x+y)^2[/tex]

[tex]2x(x+y)^2=2\times x\times (x+y)^2[/tex]

HCF of ([tex]x^3y+2x^2y^2+xy^3,2x^3+4x^2y+2xy^2[/tex])

[tex]=x(x+y)^2[/tex]

Answer:

The answer is 3.

Step-by-step explanation:

What is the difference between 8 and 5? In mathematics, the difference between two numbers usually means to subtract them. So if you want to find the difference, you take the bigger one minus the smaller one. So, the difference between 8 and 5 is 3.

Answer:

3

Step-by-step explanation:

What is the difference between 8 and 5? In mathematics, the difference between two numbers usually means to subtract them. So if you want to find the difference, you take the bigger one minus the smaller one. So, the difference between 8 and 5 is 3.

Answer:

by using middle term break method

Step-by-step explanation:

9x^2 + 12x + 4

9x^2+ (6 + 6)x + 4

9x^2 + 6x + 6x + 4

3x(3x + 2) + 2(3x + 2)

(3x + 2)(3x + 2)

(3x + 2)^2

Answer:

x = 7.2

y = 10

z = 6

Step-by-step explanation:

Since ABCD ~ JKLM, therefore, the ratio of their corresponding sides would be equal. Thus:

JK/AB = KL/BC = LM/CD = JM/AD

Substitute

12/x = y/6 = 15/9 = 10/z

✔️Find x:

12/x = 15/9

12/x = 5/3

Cross multiply

x*5 = 3*12

5x = 36

x = 36/5

x = 7.2

✔️Find y:

y/6 = 15/9

y/6 = 5/3

Cross multiply

y*3 = 5*6

3y = 30

y = 30/3

y = 10

✔️Find z:

15/9 = 10/z

5/3 = 10/z

Cross multiply

5*z = 10*3

5z = 30

z = 30/5

z = 6

The Answer is -0.985

I just took the test.

Answer:

[tex]16 {x}^{2} + 24xy + 9 {y}^{2} [/tex]

Step-by-step explanation:

U can reduce this into

[tex](4x + 3y) {}^{2} [/tex]

Which is a square.

Now,

16x^2 + 24xy + 9y^2

16x^2 + 12xy + 12xy + 9y^2

4x ( 4x + 3y ) + 3y ( 4x + 3y )

( 4x + 3y ) ( 4x + 3y )

( 4x + 3y )^2

I hope you understand...

Mark me as brainliest...

Given:

Line A goes through (0,y) and (-2,0).

Line B goes through (1,2) and (3,10).

To find:

The value of y for which the system of given linear equation (equation of line A and line B) has no solutions.

Solution:

Two linear equation has no solutions if they are parallel line.

Slope formula:

[tex]m=\dfrac{y_2-y_1}{x_2-x_1}[/tex]

We know that the slopes of two parallel lines are the same.

So, the given system of given linear equation has no solutions if

Slope of line A = Slope of line B

[tex]\dfrac{0-y}{-2-0}=\dfrac{10-2}{3-1}[/tex]

[tex]\dfrac{-y}{-2}=\dfrac{8}{2}[/tex]

[tex]\dfrac{y}{2}=4[/tex]

Multiply both sides by 2.

[tex]\dfrac{y}{2}\times 2=4\times 2[/tex]

[tex]y=8[/tex]

Therefore, the required value of y is 8.

Answer:

C)  The graph rises to the left and rises to the right.

Step-by-step explanation:

The highest expone tis even and it's coefficient is positive

therefor

The graph rises to the left and rises to the right.

Answer:

x = 2

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Distributive Property

Equality Properties

Algebra I

Step-by-step explanation:

Step 1: Define

Identify

2(x + -5) + x = x + (-6)

Step 2: Solve for x

Answer:

x=2 ( see Image below)

Step-by-step explanation:

cancel equal terms on both sides of the equation

2(x-5)=-6

move the constant to the right -hand side and change its sign

2x= -6 +10

Calculate the sum

2x=4

divide both sides of the equation by 2

x=2

Answer:

7

Step-by-step explanation:

|-7|  means find the distance from 0

We take the non negative value

|-7| = 7