2. Suppose over several years of offering AP Statistics, a high school finds that final exam scores are normally distributed with a mean of 78 and a standard deviation of 6. A. What are the mean, standard deviation, and shape of the distribution of x-bar for n

Answers

Answer 1

Answer:

By the Central Limit Theorem, the mean is 78, the standard deviation is [tex]s = \frac{6}{\sqrt{n}}[/tex] and the shape is approximately normal.

Step-by-step explanation:

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

Mean of 78 and a standard deviation of 6

This means that [tex]\mu = 78, \sigma = 6[/tex]

Samples of n:

This means that the standard deviation is:

[tex]s = \frac{\sigma}{\sqrt{n}} = \frac{6}{\sqrt{n}}[/tex]

What are the mean, standard deviation, and shape of the distribution of x-bar for n?

By the Central Limit Theorem, the mean is 78, the standard deviation is [tex]s = \frac{6}{\sqrt{n}}[/tex] and the shape is approximately normal.


Related Questions

Can someone tell me how to give the brainliest award out. You will get it if you answer first

Answers

Answer:

you click the crown :)

Step-by-step explanation:

hope this helps!

Answer:

Just click on the words "Award Brainliest" on top of the answer of a user to a certain question of yours.

Step-by-step explanation:

In a sightseeing boat near the base of the Horseshoe Falls at Niagara Falls, a
passenger estimates the angle of elevation to the top of the falls to be 30°.
If the Horseshoe Falls are 173 feet high, what is the distance from the boat
to the base of the falls?

Answers

Answer:

299.64 ft

Step-by-step explanation:

The diagrammatic representation of the problem has been attached below :

Applying trigonometry :

We use the relation :

Tanθ = opposite / Adjacent

Tan 30 = 173 / d

0.5773502 = 173 / d

0.5773502d = 173

d = 173 / 0.5773502

d = 299.64 ft

the perimeter of a square is 75 cm what is the length of one side of the square​

Answers

Answer:

length of one side = 18.75cm

Step-by-step explanation:

Perimeter of a square = 4 x side

                             75 = 4 x side

[tex]side = \frac{75}{4} = 18.75cm[/tex]                            

Find the mean of the following data set 5,9,3,12,14,67,22,45,1,12,14

Answers

Answer:

18.5 i believe

Step-by-step explanation:

sorry if im wrong, have a great day!!

Find the area of a regular polygon with 9 sides that has a side length of 12 inches and an apothem of 15 inches.​

Answers

Answer:

An apothem is a line drawn from the centerpoint of the polygon to one side of the polygon. There is a formula for area in terms of apothem:

A = (1/2)*(Perimeter)*(Apothem)

The perimeter of the regular polygon  is just the length of one side multiplied with the number of sides. Since a polygon with   9 sides,

P = 9(15) = 135in

A = 1/2 ×135 × 12

A = 810 square inches ans

If 8,a,b,27 are in geometric sequence, find the value of a and b.​

Answers

Answer:

a = 12 and b = 18

Step-by-step explanation:

Given that,

8,a,b,27 are in geometric sequence.

For a GP, the nth term is given by :

[tex]a_n=ar^{n-1}[/tex]

Put n = 4

[tex]a_4=ar^{4-1}\\\\a_4=ar^3\\\\27=8\times r^3\\\\r^3=\dfrac{27}{8}\\\\r=\dfrac{3}{2}=1.5[/tex]

Put n = 2,

[tex]a_2=ar^{2-1}\\\\a=ar\\\\a=8\times 1.5\\\\a=12[/tex]

Put n = 3

[tex]a_3=ar^2\\\\=8\times 1.5^2\\\\b =18[/tex]

So, the values of a and b is 12 and 18 respectively.

Which coordinate point represents the y -intercept of the equation 3x + 2y = 18

Answers

Answer:

(-6,18)

Step-by-step explanation:

3x + 2y = 18

2y= -3x + 18

y=-3/2 x + 18

give x=0

y=-3/2 *0+18

y=18#

y=18

3x+2(18)=18

3x+36=18

3x=18-36

3x=-18

x=-18/3

x=-6

The question is in the picture (:

Answers

Answer:

[tex] \frac{(x - 2)(x + 2)}{x - 8} [/tex]

That’s answer is correct

What type of symmetry’s are shown?

Answers

Answer:

18o rotational symetry  

Step-by-step explanation:

Insurance companies are interested in knowing the population percent of drivers who always buckle up before riding in a car. They randomly survey 387 drivers and find that 298 claim to always buckle up. Construct a 84% confidence interval for the population proportion that claim to always buckle up.

Answers

Answer:

The 84% confidence interval for the population proportion that claim to always buckle up is (0.74, 0.80).

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.

[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

In which

z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].

They randomly survey 387 drivers and find that 298 claim to always buckle up.

This means that [tex]n = 387, \pi = \frac{298}{387} = 0.77[/tex]

84% confidence level

So [tex]\alpha = 0.16[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.16}{2} = 0.92[/tex], so [tex]Z = 1.405[/tex].

The lower limit of this interval is:

[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.77 - 1.405\sqrt{\frac{0.77*0.23}{387}} = 0.74[/tex]

The upper limit of this interval is:

[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.77 + 1.405\sqrt{\frac{0.77*0.23}{387}} = 0.8[/tex]

The 84% confidence interval for the population proportion that claim to always buckle up is (0.74, 0.80).

(1 point) Some shrubs have the useful ability to resprout from their roots after their tops are destroyed. Fire is a particular threat to shrubs in dry climates, as it can injure the roots as well as destroy the aboveground material. One study of resprouting took place in a dry area of Mexico. The investigation clipped the tops of samples of several species of shrubs. In some cases, they also applied a propane torch to the stumps to simulate a fire. Of 16 specimens of a particular species, 7 resprout after fire. Estimate with 99% confidence the proportion of all shrubs of this species that will resprout after fire.

Answers

Answer:

The answer is "[tex]0.45 \pm 0.18204[/tex]"

Step-by-step explanation:

For the +4 sample proportion[tex]= \frac{(7+2)}{(16+4)} = \frac{9}{20} = 0.45[/tex]

Sample percentage measurements estimated stdev

[tex]= \sqrt{\frac{[(0.45)(1-0.45)]}{[(16+4)]}}\\\\ = \sqrt{\frac{[(0.45)(0.55)]}{[(20)]}}\\\\ = \sqrt{\frac{0.2475}{20}}\\\\= \sqrt{0.012375}\\\\=0.111[/tex]

Calculating the critical z for a=0.1, two-tailed = 1.64

Calculating the confidence interval:

[tex]= 0.45 \pm 0.111 \times 1.64 \\\\= 0.45 \pm 0.18204[/tex]

Mary’s bedroom rug is shown below. Find the perimeter and area of the rug.

Answers

Can’t see the question

1/4 x 1/6 x 1/12= What fraction did Phil eat of the pizza

Answers

Answer:

[tex] \frac{1}{288} [/tex]

Step-by-step explanation:

the 1 will always stay the same because all of them are 1's

4×6=24

24×12=288

Answer:

garage bozo

Step-by-step explanation:

I need help on this question

Answers

Answer:

A

Step-by-step explanation:

What are the coordinates of the solution of these two linear equations

Answers

Answer:

(-2 -3)

Step-by-step explanation:

_____________________

a serving of crackers has 1.5 grams of fat. How many grams of fat are in 3.75 servings

Answers

Answer:

5.625

Step-by-step explanation:

You just have to multiply 1.5 by 3.75 which is 5.625.

So there are 5.625 grams of fat in 3.75 servings.

5.625 grams of fat are in 3.75 servings.

You just have to multiply 1.5 by 3.75 which is 5.625.

So there are 5.625 grams of fat in 3.75 servings.

What is a Unitary method?

The unitary method is a technique for solving a problem by first finding the value of a single unit, and then finding the necessary value by multiplying the single unit value.

Learn more about the unitary method here https://brainly.com/question/24587372

#SPJ2

Todd Lyle worked Monday through Friday from 8:00 A.M. to 5:00 P,M. with an hour off for lunch. He is paid $10,50 an hour. Find his earnings for the week.

Answers

Answer:

$315

Step-by-step explanation:

He earns $63 everyday, and then you just have to multiply that by 5 since he works 5 days in a week.

Find the exact value of tan A in simplest radical form.
PLEASE HELP

Answers

Answer:

[tex] \tan(A) = \frac{opp}{adj} \\ \tan(A) = \frac{ \sqrt{72} }{3} \\ \tan(A) = \frac{ \sqrt{36 \times 2} }{3} \\ \tan(A) = \frac{6 \sqrt{2} }{3} \\ \tan(A) = 2 \sqrt{2} [/tex]

67-2x+89/2+7-8x=0
help me please​

Answers

Answer:

x = 11.85

Step-by-step explanation:

[tex]67 - 2x + \frac{89}{2} + 7 -8x = 0\\\\67 + \frac{89}{2}+7 = 8x + 2x\\\\\frac{134 + 89 +14}{2} = 10x\\\\10x = 118.5\\\\x = 11.85[/tex]

Answer:

[tex]x = 11 \frac{17}{20}[/tex] or [tex]\frac{237}{20}[/tex]

Step-by-step explanation:

Isolate the variable by dividing each side by factors that don't contain the variable.

Express 5 cm in metre and kilometre.in decimals........................

Answers

Answer:

0.05 metre

5×10^5 kilometer

1.9685

In Δ Q R S s = 7.9 cm ∠ Q = 125 ∘ and ∠ R = 23 ∘ '. Find the length of q, to the nearest 10th of a centimeter.

Answer- 12.2

Answers

Answer:

See the attachment ⬆️⬆️

Complete the comparison 5+4. A.9+1. B.10+0.C.5-4.D.15-4

Answers

Answer:

A.5+4<9+1

B. 5+4<10+0

C. 5+4>5-4

D. 5+4=15-4

Step-by-step explanation:

A. 9<10

B. 9<10

C. 9>1

D9=9

Answer:

A=10>5+4

B=10>5+4

C=1<5+4

D=11>5+4

Step-by-step explanation:

Patel made a rectangular garden in his family's backyard. 24 ft What is the perimeter of the garden? A 336 feet B 76 feet C 48 feet D 38 f​

Answers

Answer:

336+76+48+38= 498

Step-by-step explanation:

add all those sides up because it is just the perimeter

Answer:

336+76+48+38= 498

Step-by-step explanation:

fx= ab*2÷t*2, make t the subhect of the formulae
[tex]fx = ab { }^{2} \div t {?}^{2} [/tex]

Answers

Answer:

t = √ab²/fx

Step-by-step explanation:

fx= ab*2÷t*2, make t the subject of the formulae

​Given the function

fx = ab²/t²

We are to make t the subject of the formula

fxt² = ab²

t² = ab²/fx

Take the square root of both sides

√t² = √ab²/fx

t = √ab²/fx

Hence the required value of t is √ab²/fx

Find the circumference of a circle with a radius of 6 cm.



Hi besties i need. help ASAP please and. ty ​

Answers

Answer:

37.7

Step-by-step explanation:

Circumference = [tex]2\pi r[/tex]

Circumference = [tex](2)(\pi )(6)[/tex]

Circumference = 37.69911184 / 37.7

Therefore, circumference of the circle with the radius 6 cm is 37.7.

Answer:

37.7

Step-by-step explanation:

formula for circumference of a circle=2πr

2×π×6=37.7cm

Which of the following plots has exactly 2 clusters and
1 outlier

Answers

The plot that best fits into that description would be “A (top left graph)”

45-45-90 Right Triangles! Can somebody please help me? ASAP!!

Answers

Answer:

Step-by-step explanation:

45-45-90 triangles always have the same relationships

leg = x,    hypotenuse = x√2

If you have the leg length multiply it by √2 to get the hypotenuse

hypotenuse = x,   Leg = x/√2

If you have the hypotenuse length divide it by √2 to get the leg

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

7)

leg  = 3√2 / 2

hyp =  3√2 / 2 *  √2 = 3

8)

leg = 5√2

hyp = 5√2 *√2 = 10

9)

hyp = 2

leg = 2 / √2 = √2

10)

leg = 13√2 / 2

hyp = 13√2 / 2 * √2  = 13

11)

leg = 3√3

hyp = 3√3 * √2 = 3√6

12)

leg = 12

hyp = 12√2

Anna bought 3 types of fruit for a fruit salad. She paid three times as much for blueberries as for pears and $2.50 less for strawberries than for blueberries.
If The total cost was $13.25 how much did Anna spend on each type of fruit

Answers

Answer:

Anna spent $ 2.25 on pears, $ 6.75 on blueberries, and $ 4.25 on strawberries.

Step-by-step explanation:

Given that Anna bought 3 types of fruit for a fruit salad, and she paid three times as much for blueberries as for pears and $ 2.50 less for strawberries than for blueberries, if the total cost was $ 13.25, to determine how much did Anna spend on each type of fruit, the following calculation must be performed:

Pears: X

Blueberries: 3X

Strawberries: 3X - 2.5

X + 3X + 3X - 2.5 = 13.25

7X = 13.25 + 2.5

X = 15.75 / 7

X = 2.25

Pears: 2.25

Blueberries: 3 x 2.25 = 6.75

Strawberries: 3 x 2.25 - 2.50 = 6.75 - 2.50 = 4.25

2.25 + 6.75 + 4.25 = 13.25

Therefore, Anna spent $ 2.25 on pears, $ 6.75 on blueberries, and $ 4.25 on strawberries.

Write the meaning of each algebraic expression. Then, evaluate the algebraic expression for the given value.
5x - 4 If x=3

Answers

In mathematics, an algebraic expression is an expression built up from integer constants, variables, and the algebraic operations (addition, subtraction, multiplication, division and exponentiation by an exponent that is a rational number). For example, 3x2 − 2xy + c is an algebraic expression.

5x−4x=3

Step 1: Simplify both sides of the equation.

5x−4x=3

5x+−4x=3

(5x+−4x)=3(Combine Like Terms)

x=3

x=3

Answer:

x=3

HELP
Which equation has no real solution A. B2 + 3b = -3
B. 2c2 + 4c = 9
C. -5c2 – c= -2
D.7g +1 + 3g2 = 0

Answers

Answer:

A.

[tex] {b}^{2} + 3b - 3 = 0[/tex]

Step-by-step explanation:

[tex] {b}^{2} + 3b - 3 = 0 \\ because \: \: {b}^{2} < 4ac \\ {b}^{2} = {3}^{2} = 9 \\ 4ac = 4 \times 1 \times - 3 = - 12 \\ hence : {b}^{2} < 4ac[/tex]

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does anybody know how to solve this problem? how do i find the unit rate? someone help please hey! ill give brainliest please help What is the molarity of a solution containing 9.0 moles of solute in 462 mL of solution Find the lengths of a square having area 676cm2 Read this dictionary entry.lead (leed) noun1. the first or foremost place 2. a leash 3. a piece of information that helps guide; a tip or clue 4. a guide or indication of a road or courseRead this sentence from the article.While giving tours, he spotted many leads off the main passages.Which meaning best fits the way the word leads is used in the sentence above?F. meaning 1G. meaning 2H. meaning 3I. meaning 4Please help if i dont score 70% or higher im gonna stay back There are 15 plates in the kitchen cabinet. The diameter of each plate is either 9 inches or 12 inches. The diameter of all 15 plates combined is 150 inches.Which system of equations can be used to find the number of 9-inch plates, x, and the number of 12-inch plates, y, that are in the cabinet? Which expression represents the area of the square?A: 4.4B:2+4C:2.4Or C: 4+ 4 help pls? In the morning, the temperature was 10C. By the afternoon, it had risen to 2C. What was the change in temperature from the morning to the afternoon? explain why it is important to cool down after exercise due today, almost midnight The colonies had the strongest navy in the world due to proximity to the Atlantic ocean true or false A chemist performs the same tests on two white solids, A and B. The results are shown in the table below.imageWhich result identifies the substances, A and B, correctly? I NEED HELP ASAPPP!! Pleasee Describe a few of the external stressors we can experience in life and why they cause us stress. Help pls im taking the test hurry plssssss thank u Mary and her dad shared one dozen brownies 2/6 of them have nuts which dad dosent 4 eat how many brownies did dad not eat because they had nuts Describe one political, one economic, and one social way the world changedbetween 1914 and 2001, and explain the impact of those three changes. Which algebraic expression below represents four multiplied by a number? A. 4 x B. x + 4 C. 4x D. Which invention enabled the discovery of bacteria?