Adam tabulated the values for the average speeds on each day of his road trip as 60.5, 63.2, 54.7, 51.6, 72.3, 70.7, 67.2, and 65.4 mph. The sample standard deviation is 7.309.Select the 98% confidence interval for Adam’s set of data.a. 46.94 to 71.33b. 46.94 to 79.46c. 55.45 to 79.46d. 55.45 to 70.95

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:

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:

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:

x² + 3x - 10 = 0

x² - 25 = 0

Answer:

x ≥ 12

Step-by-step explanation:

-3/4x +2 ≤ -7

Subtract 2 from each side

-3/4x +2-2 ≤ -7-2

-3/4x  ≤ -9

Multiply each side by -4/3, remembering to flip the inequality

-3/4x * -4/3 ≥ - 9 *(-4/3)

x ≥ 12

Answer:

x>=12

Step-by-step explanation:

-3/4x + 2<=-7

-3/4x <= -7 -2

-3/4x<=-9

cross multiply

-3x<=-36

dividing throughout by -3

x>=12

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

Answer:

216

Step-by-step explanation:

=>log   36 = -2/3

        m

=>36=(m)^-2/3

=>(root(-36))^3=m

=>m=(root(36))^3

=>m=6^3

=>m=216

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:

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:

Hi im not got with graphs

Step-by-step explanation:

Answer:

21 times 660 and then you will get the answer

5 ÷ 1/2 => 5 x 2/1 => 10/1 => 10

Answer:

10

Step-by-step explanation:

In the pic, it shows ten half squares.  

Answer is

5 gives the range of possible values for x.

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:

Because we know that here we have an oscillation, we can model this with a sine or cosine function.

P = A*cos(k*t) + M

where:

k is the frequency

A is the amplitude

M is the midline

We know that at t = 0, we have the lowest population.

We know that the mean is 129, so this is the midline.

We know that the population oscillates 25 above and below this midline,

And we know that for t = 0 we have the lowest population, so:

P = A*cos(k*0) + 129 = 129 - 25

P = A + 129 = 129 - 25

A = -25

So, for now, our equation is

P = -25*cos(k*t) + 129

Because this is a yearly period, we should expect to see the same thing for t = 12 (because there are 12 months in one year).

And remember that the period of a cosine function is 2*pi

Then:

k*12 = 2*pi

k = (2*pi)/12 = pi/6

Finally, the equation is:

P = -25*cos(t*pi/6) + 129

Now we want to find the lowest population was in April instead:

if January is t = 0, then:

February is t = 2

March is t = 3

April is t = 4

Then we would have that the minimum is at t = 4

If we want to still use a cosine equation, we need to use a phase p, such that now our equation is:

P = -25*cos(k*t + p) + 129

Such that:

cos(k*4 + p) = 1

Then:

k*4 + p = 0

p =  -k*4

So our equation now is:

P = -25*cos(k*t  - 4*k) + 129

And for the periodicity, after 12 months, in t = 4 + 12 = 16, we should have the same population.

Then, also remembering that the period of the cosine function is 2*pi:

k*12 - 4*k = 2*pi

k*8 = 2*pi

k = 2*pi/8 = pi/4

And remember that we got:

p = -4*k = -4*(pi/4) = -pi

Then the equation for the population in this case is:

P = -25*cos( t*pi/4 - pi) + 129

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:

[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...

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

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

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:

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:

7

Step-by-step explanation:

|-7|  means find the distance from 0

We take the non negative value

|-7| = 7

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:

It will take him 5.85 seconds.

Step-by-step explanation:

12.5 (0.2t - 1) + 21t = 150

Use Distributive Property:

2.5t - 12.5 + 21t = 150

Combine like terms:

23.5t - 12.5 = 150

Subtract 12.5 from both sides:

23.5t = 137.5

Divide both sides by 23.5 to isolate variable t:

5.851063.....

Round to two decimal places (hundredths place):

5.85

Answer:

Step-by-step explanation:

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:

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