In 2008 the Better Business Bureau settled 75% of complaints they received (USA Today, March 2, 2009). Suppose you have been hired by the Better Business Bureau to investigate the complaints they received this year involving new car dealers. You plan to select a sample of new car dealer complaints to estimate the proportion of complaints the Better Business Bureau is able to settle. Assume the population proportion of complaints settled for new car dealers is .75, the same as the overall proportion of complaints settled in 2008
a. Suppose you select a sample of 450 complaints involving new car dealers. Show the sampling distribution of .
b. Based upon a sample of 450 complaints, what is the probability that the sample proportion will be within .04 of the population proportion?
c. Suppose you select a sample of 200 complaints involving new car dealers. Show the sampling distribution of .
d. Based upon the smaller sample of only 200 complaints, what is the probability that the sample proportion will be within .04 of the population proportion?
e. As measured by the increase in probability, how much do you gain in precision by taking the larger sample in part (b)?

Answers

Answer 1

Answer:

Explained below.

Step-by-step explanation:

According to the Central limit theorem, if from an unknown population large samples of sizes n > 30, are selected and the sample proportion for each sample is computed then the sampling distribution of sample proportion follows a Normal distribution.

The mean of this sampling distribution of sample proportion is:

 [tex]\mu_{\hat p}= p[/tex]

The standard deviation of this sampling distribution of sample proportion is:

 [tex]\sigma_{\hat p}=\sqrt{\frac{p(1-p)}{n}}[/tex]

(a)

The sample selected is of size n = 450 > 30.

Then according to the central limit theorem the sampling distribution of sample proportion is normally distributed.

The mean and standard deviation are:

[tex]\mu_{\hat p}=p=0.75\\\\\sigma_{\hat p}=\sqrt{\frac{p(1-p)}{n}}=\sqrt{\frac{0.75(1-0.75)}{450}}=0.0204[/tex]

So, the sampling distribution of sample proportion is [tex]\hat p\sim N(0.75,0.0204^{2})[/tex].

(b)

Compute the probability that the sample proportion will be within 0.04 of the population proportion as follows:

[tex]P(p-0.04<\hat p<p+0.04)=P(\frac{-0.04}{0.0204}<\frac{\hat p-p}{\sigma_{\hat p}}<\frac{0.04}{0.0204})[/tex]

                                          [tex]=P(-1.96<Z<196)\\=P(Z<1.96)-P(Z<-1.96)\\=0.975-0.025\\=0.95[/tex]

Thus, the probability that the sample proportion will be within 0.04 of the population proportion is 0.95.

(c)

The sample selected is of size n = 200 > 30.

Then according to the central limit theorem the sampling distribution of sample proportion is normally distributed.

The mean and standard deviation are:

[tex]\mu_{\hat p}=p=0.75\\\\\sigma_{\hat p}=\sqrt{\frac{p(1-p)}{n}}=\sqrt{\frac{0.75(1-0.75)}{200}}=0.0306[/tex]

So, the sampling distribution of sample proportion is [tex]\hat p\sim N(0.75,0.0306^{2})[/tex].

(d)

Compute the probability that the sample proportion will be within 0.04 of the population proportion as follows:

[tex]P(p-0.04<\hat p<p+0.04)=P(\frac{-0.04}{0.0306}<\frac{\hat p-p}{\sigma_{\hat p}}<\frac{0.04}{0.0306})[/tex]

                                          [tex]=P(-1.31<Z<196)\\=P(Z<1.31)-P(Z<-1.96)\\=0.9049-0.0951\\=0.8098\\\approx 0.81[/tex]

Thus, the probability that the sample proportion will be within 0.04 of the population proportion is 0.81.

(e)

The probability that the sample proportion will be within 0.04 of the population proportion if the sample size is 450 is 0.95.

And the probability that the sample proportion will be within 0.04 of the population proportion if the sample size is 200 is 0.81.

So, there is a gain in precision on increasing the sample size.


Related Questions

what is the slope of a line parallel to the line whose equation is 3x - 2y = 18

Answers

Answer:

3/2

Step-by-step explanation:

3x - 2y = 18

y=(3/2)x-9

Slope of the given line=3/2

As parallel lines have same slope, slope of the line parallel to the line 3x - 2y = 18 is 3/2.

Hope it helps :)

Slope of a line parallel to the line whose equation is 3x - 2y = 18 is 3/2.

What is Slope of Line?

The slope of the line is the ratio of the rise to the run, or rise divided by the run. It describes the steepness of line in the coordinate plane.

The slope intercept form of a line is y=mx+b, where m is slope and b is the y intercept.

The slope of line passing through two points (x₁, y₁) and (x₂, y₂) is

m=y₂-y₁/x₂-x₁

Two lines are said to be parallel when their slopes are same.

To find the slope of parallel line, we need to find slope of 3x - 2y = 18

3x-2y=18

-2y=18-3x

y=-18/2+3/2x

y=3/2x-18/2

Slope of line is 3/2

Hence, slope of a line parallel to the line whose equation is 3x - 2y = 18 is 3/2.

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A cartographer creates a map of Bucks County with a scale factor of 1 inch = 10 miles. The distance between Quakertown and Sellerville is 2.92 inches on the map. Determine the actual distance between the two boroughs.​

Answers

3 inches i think if im wrong then oof

FOR EXAMPLE:

Christa and her family went out for pizza and it cost $28. In Tennessee we have a sales tax that is 7% which has to be paid along with $28. What is the sales tax on $28?

Answers

7% of 28$ is $1.96. Hope that helps

Parker invests $1000 for 5 years at a simple rate of 10%.

A. How much interest will Parker earn after 5 years?

B. What will be the total amount that Parker will have after 5 years?

Answers

Answer:

SI=PTR/100

= 1000×5×10/100

=$500

Parker will receive $500 as interest.

Amount=$500+$1000

=$1500

Parker will have $1500 altogether.

An "extreme" pogo stick utilizes a spring whose uncompressed length is 46 cm and whose force constant is 1.4 x 104 N/m. A 60-kg person is jumping on the pogo stick, compressing the spring to a length of only 5.0 cm at the bottom of their jump. Which is the upward acceleration of the person at the moment the spring reaches its greatest compression at the bottom of their jump?
a. 96 m/s^2
b. 86 m/s^2
c. 976 m/s^2
d.860 m/s^2

Answers

Answer:

B. [tex]86\,\frac{m}{s^{2}}[/tex]

Step-by-step explanation:

From Newton's Laws of Motion, the spring is compressed against effects of weight of the person and as sping force is a restitutive force, the net force experimented by person is different from zero. By applying Second Newton's Law, we get this equation of equilibrium on person:

[tex]\Sigma F = k\cdot \Delta x -m\cdot g = m\cdot a[/tex] (Eq. 1)

Where:

[tex]k[/tex] - Spring constant, measured in newtons per meter.

[tex]\Delta x[/tex] - Change in the length of spring, measured in meters.

[tex]m[/tex] - Mass of the person, measured in meters.

[tex]g[/tex] - Gravitational acceleration, measured in meters per square second.

[tex]a[/tex] - Net acceleration of the person, measured in meters per square second.

Now we proceed to clear net acceleration:

[tex]a = \frac{k}{m}\cdot \Delta x -g[/tex]

If we know that [tex]k = 1.4\times 10^{4}\,\frac{N}{m}[/tex], [tex]m = 60\,kg[/tex], [tex]\Delta x = 0.41\,m[/tex] and [tex]g = 9.807\,\frac{m}{s^{2}}[/tex], the acceleration of the person when spring reaches its greatest compression at the bottom of their jump is:

[tex]a = \frac{1.4\times 10^{4}\,\frac{N}{m} }{60\,kg} \cdot (0.41\,m)-9.807\,\frac{m}{s^{2}}[/tex]

[tex]a = 85.859\,\frac{m}{s^{2}}[/tex]

Which corresponds to option B.

Consider the line -7x - 5y=4.

Answers

y= 4+7x/-5 is the answer of you're asking to solve

Which of the following statements describes the value of the expression 35 – 2x, when x = 6?
A) It is a prime number
B) It is a composite number
C) It is a whole number that is neither prime nor composite
D) It is not a whole number.

Answers

Answer: B

Step-by-step explanation: 3x3=9 1x9 equals 9 if a number has 2 or more sets, it's a composite number. It would not become prime because 9 does not have 1 set.

Answer:

Step-by-step explanation:

b

How can a transformed quadratic equation be used real life situation?​

Answers

Answer:

Quadratic equations are actually used in everyday life, as when calculating areas, determining a product's profit or formulating the speed of an object. Quadratic equations refer to equations with at least one squared variable, with the most standard form being ax² + bx + c = 0.

Step-by-step explanation:

A car sharing service offers a membership plan with a $50 per month fee that includes 10 hours of driving each month and charges $9 for each additional hour
(A) Write a piecewise definition of the cost F(x) for a month in which a member uses a car for x hours
(B) Graph F(x) for 0 < x s 15
(C) Find lim x--->10 F(x), lim x--->10F(x), and lim x--->10F(x), which- ever exist.

Answers

Answer:

A)  F(x) = 50 + ( x - 10 )*9  

B) Graph

C) lim ( x ⇒ 10) F(x) = 50

Step-by-step explanation:

A) F(x) = 50 + ( x - 10 )*9       since the first 10 hours are included in initial fee

B) In Annex

C) lim (x ⇒ 10) F(x) = 50 + ( 10 -10)*9

lim ( x ⇒ 10) F(x) = 50 + 0

lim ( x ⇒ 10) F(x) = 50

Research shows that many banks are unwittingly training their online customers to take risks with their passwords and other sensitive account information, leaving them more vulnerable to fraud (Yahoo, July 23, 2008). Even web-savvy surfers could find themselves the victims of identity theft because they have been conditioned to ignore potential signs about whether the banking site they are visiting is real or a bogus site served up by hackers. Researchers at the University of Michigan found design flaws in 78% of the 214 U.S. financial institution websites they studied.

Required:
Is the sample evidence sufficient to conclude that more than three out of four financial institutions that offer online banking facilities are prone to fraud? Use a 5% significance level for the test.

Answers

Answer:

Decision rule

Fail to reject the null  hypothesis

Conclusion

The sample evidence is not sufficient to conclude that more than three out of four financial institutions that offer online banking facilities are prone to fraud.

Step-by-step explanation:

From the question we are told that

  The sample size is  n =  214

   The sample proportion is p = 0.78

   The level of significance is [tex]\alpha = 0.05[/tex]

Generally the population proportion is mathematically represented as

      [tex]p = \frac{3}{4} =0.75[/tex] (gotten from the statement  ''three out of four'' in the question)

The null hypothesis is [tex]H_o : p = 0.75[/tex]

The alternative hypothesis [tex]H_a : p > 0.75[/tex]

Generally the test statistics is mathematically represented as

     [tex]z = \frac{\^{p} - p}{ \sqrt{\frac{p(1-p)}{n} } }[/tex]

=>    [tex]z = \frac{0.78- 0.75}{ \sqrt{\frac{ 0.75(1-0.75)}{214} } }[/tex]

=>  [tex]z = 1.01[/tex]

Generally the p-value is mathematically represented as

    [tex]p-value  = P(Z > z )[/tex]

=> [tex]p-value  = P(Z > 1.01 )[/tex]

From the z-table  

    [tex]P(Z > 1.01 ) = 0.15625[/tex]

So

    [tex]p-value  = 0.15625 [/tex]

From the obtained values we see that [tex]p-value > \alpha[/tex] hence we fail to reject the null hypothesis

 Therefore we can conclude that the sample evidence is  not  sufficient to conclude that more than three out of four financial institutions that offer online banking facilities are prone to fraud.

Help out asap please!

Answers

Answer:1<x_<6 and the third line thing w the open circle (1) connecting to closed circle (6)

Step-by-step explanation:subtract 5 from both sides,

i need help plz 4z+2=34

Answers

Answer:

It's 8.

Step-by-step explanation:

I have a calculator from my school and I solved it on the calculator.

a. For what values of k does the function y = cos(kt) satisfy the differential equation 25y'' = −16y?
b. For those values of k, verify that every member of the family of functions y = A sin(kt) + B cos(kt) is also a solution.

Answers

Answer:

Step-by-step explanation:

Given y = coskt

y' = -ksinkt

y'' = -k²coskt

Substitute this y'' into the expression 25y'' = −16y

25(-k²coskt) = -16(coskt)

25k²coskt = 16(coskt)

25k² = 16

k² = 16/25

k = ±√16/25

k = ±4/5

b) from the DE 25y'' = −16y

Rearrange

25y''+16y = 0

Expressing using auxiliary equation

25m² + 16 = 0

25m² = -16

m² = -16/25

m = ±4/5 I

m = 0+4/5 I

Since the auxiliary root is complex number

The solution to the DE will be expressed as;

y = Asinmt + Bsinmt

Since k = m

y = Asinkt+Bsinkt where A and B are constants

also this one! :( pls help again! thanks.

Answers

Answer:

9 is the answer

GIVING 75 POINTS


Solve the equation from Part C so that y is by itself on one side of the equation. How are this equation and the equation of the line related? What does this relationship mean about any triangle created using this line?


Part C ---- For similar triangles, the side lengths are proportional. So, you can write a proportion relating the two pairs of vertical and horizontal side lengths. For the line y = 2x, a triangle can be drawn 2 units up and 1 unit right from the origin.



Write a proportion relating the side lengths of the triangle to any other triangle that has the line as a hypotenuse, a horizontal length of x units, and a vertical length of y units.

Answers

Answer:

This is my answer,

Step-by-step explanation:

The equation is y=2x, and the horizontal line will always be half of the vertical line (1:2). We can prove this by plugging in y or x. For example, if y is 12, 12=2x. X would equal six.

11.0.
Number o
In 6-card poker, played with a standard 52-card deck, 52Cg, or 20,358,520, different
hands are possible. The probability of being dealt various hands is the number of
different ways they can occur divided by 20,358,520. Shown to the right is the number
of ways a particular type of hand can occur and its associated probability. Find the
probability of not being dealt this type of hand.
The probability is (Round to six decimal places as needed.)
Privacy & cookies
and then click Check Answer

Answers

Using it's concept, it is found that there is a 0.999409 = 99.9409% probability of not being dealt this type of hand.

What is a probability?

A probability is given by the number of desired outcomes divided by the number of total outcomes.

In this problem, there are 20,358,520 different outcomes. The given outcome can happen in 1024 ways, and we want to find the probability of it's complement, hence those are the non-desired outcomes and the probability is:

p = (20,358,520 - 1,2024)/20,358,520 = 0.999409.

0.999409 = 99.9409% probability of not being dealt this type of hand.

More can be learned about probabilities at https://brainly.com/question/14398287

Which one of these relationships is different than the other three?



Group of answer choices

A

B

C

D


help!!!1

Answers

Where are the questionsssss?

Answer:

B

Step-by-step explanation:

I got this by looking at the graph and the numbers that I got vertically and horizontally I divided them .

what are the slopes of the two lines?
green has two yellow dots.

Answers

Answer:

-7(1/7) = -1

Step-by-step explanation:

For w(x)=-2x+7, find the value of x which w(x)=-3

Answers

Answer:

x = 5

Step-by-step explanation:

-3 = -2x+7

-10 = -2x

5 =x

The value of x from the given function is 5.

The given function is w(x)=-2x+7..

What is the function?

Functions are the fundamental part of the calculus in mathematics. The functions are the special types of relations. A function in math is visualized as a rule, which gives a unique output for every input x.

Now, put w(x)=-3 in the function and simplify.

That is, -3=-2x+7

⇒ 2x=7+3

⇒ 2x=10

⇒ x=5

Therefore, the value of x from the given function is 5.

To learn more about the function visit:

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There are approximately 330,000,000 cubic miles of water on Earth. A cubic mile is approximately 147,200,000,000 cubic feet. How much water is on Earth? Estimate using scientific notation

Answers

Answer: 4.8576 × 10^19 cubic feet of water.

Step-by-step explanation:

330m * 147.2b = 48 quintillion feet.

Answer:

5 x 10^19 ft^3

Step-by-step explanation:

Practice Makes Perfect
This practice exercise should be done by the students independently, after
completing the chapter.
1. Discover the pattern and extend it.
ABC
CBA
DEF
FED
b.
18A
20B
22C
24D
D001
001
0001
C.
460
4400
4200
40000
d.
9Z
15Y
21X
27W​

Answers

Answer:

A.

ABC

CBA

DEF

FED

Step-by-step explanation:

I hope it's help

#lets_help_each_other

is this a equation or expression 4r+3=12

Answers

Answer:

Equation

Step-by-step explanation:

Because there is only one unknown term in it

I hope it helps

Thank U

The low temperatures for three consecutive days were -5F, 3F, and 4F.Which temperature has the greatest absolute value

Answers

Answer: -5°F

Step-by-step explanation:

Absolute value makes any number positive, regardless of signs.

Therefore, -5°F has the highest absolute value because it will equal 5 which is greater than 3°F and 4°F.

Hope this helps!

I don’t understand this

Answers

Answer:

9 to the 5th power

Step-by-

Answer:

n=5  I think...

Step-by-step explanation:

9^7/9^n = 9^2

Multiply by (n)

9^7-n = 9^2

7-n=2

7-n=2: n=5

-n=-5

Simplify:

n=5

Helpppp!!!! Plzzzzzzzzz

Answers

Answer:

false

Step-by-step explanation:

Answer:

false

Step-by-step explanation:

the intersection of two planes is a line. Planes are like grids so if you have a 3d model, they'd create a line

I need help please ​

Answers

The value of X must be 0. Hope this helps and a Brainliest would be appreciated

Suppose that you roll a die 8 times. What is the probability that you roll a six three or fewer times

Answers

Answer:

0.96

Step-by-step explanation:

Given that the a die is rolled 8 number of times.

[tex]n[/tex] = 8

Probability of getting a 6 on roll of a die,  [tex]p=\frac{1}{6}[/tex]

Probability of not getting a 6 on roll of a die,  [tex]q=1-p=1-\frac{1}{6}=\frac{5}{6}[/tex]

Probability of getting 6 three or fewer times:

[tex]P(r \le 3)=P(r=0)+P(r=1)+P(r=2)+P(r=3)[/tex]

Formula:

[tex]P(r=k)=_nC_k.p^k.q^{n-k}[/tex]

Putting the values using this formula:

[tex]P(r \le 3)=_8C_0.\frac{1}{6}^0.\frac{5}{6}^{8-0}+_8C_1.\frac{1}{6}^1.\frac{5}{6}^{8-1}+_8C_2.\frac{1}{6}^2.\frac{5}{6}^{8-2}+_8C_3.\frac{1}{6}^3.\frac{5}{6}^{8-3}\\\Rightarrow P(r \le 3)=1.\frac{5}{6}^{8}+8.\frac{1}{6}.\frac{5}{6}^{7}+28.\frac{1}{36}^2.\frac{5}{6}^{6}+56.\frac{1}{216}.\frac{5}{6}^{5}\\\Rightarrow P(r \le 3)=0.23+0.37+0.26+0.1=\bold{0.96}[/tex]

please help my geometry assginment, brainly if answer properly

Answers

Answer:

Please mark me brainliest     :)   Hope it helps

Step-by-step explanation:

So basically, since CD and AB are parallel, that means that angle2 and angle3 are similar, due to the corresponding angle postulate. Furthermore, it is given that AG and CE are similar, so angle1 and angle2 are similar on the same principle.

This means that angle3 and angle4 are similar, since it is given that angle1 and angle4 are similar. A bisecting line divides a whole angle into two, equal value angles, and since ECF is composed of angle3 and angle4, and angle3 and angle4 are the same value, that means the line that forms angle3 and angle4 is bisecting the ECF, therefore CD bisects ECF.

please i need in under 20 mintute quick

Answers

Answer:

its been over twenty minutes. did you figure it out ?

What are reasons A, B, and C in the proof?

Prove: (4 · 3)l + (2 · 4)l = 20l

Statements Reasons
(4 · 3)l + (2 · 4)l = (4 · 3)l + (4 · 2)l A. _________________
= 4(3l + 2l) B. _________________
= 4(5l) Addition
= (4 · 5)l C. _________________
= 20l Multiplication

Answers

Answer:

A. Commutative property

B. Associative and distributive properties.

C. Associative property.

Step-by-step explanation:

We proceed to present which reason are utilized by supporting procedure:

1) [tex](4\cdot 3) \cdot i +(2\cdot 4)\cdot i[/tex] Given

2) [tex](4\cdot 3)\cdot i +(4\cdot 2)\cdot i[/tex] A. Commutative property

3) [tex]4\cdot (3\cdot i+2\cdot i)[/tex] B. Associative and distributive properties.

4) [tex]4\cdot (5\cdot i)[/tex] Addition.

5) [tex](4\cdot 5)\cdot i[/tex] C. Associative property.

6) [tex]20\cdot i[/tex] Multiplication/Result.

Other Questions
put this numbers from greatest to least0.2734, 23.74, 0.0347, 0.43,0.0043 HURRY PLEASE!! Ill mark you as brainliestWhich graph shape would represent the connectedpoints in Celeste's function table?A. A straight line that slopes up from left to rightB. A straight line that slips down from left to rightC. A symmetrical V shape that opens downD. A symmetrical face shape that opens up Identify which account would be debited and credited to record each transaction occurred at Forever Green Lawn Service. The first transaction has been completed as an example. Transactions Debit Credit Ex. Issued a check for monthly rent. Rent Expense Cash 1. Purchased supplies on account. Supplies Accounts Payable 2. Purchased new equipment, issuing a check for a down payment, with balance due in thirty days. Equipment Cash, Accounts Payable 3. Provided services on account. Accounts Receivable Fees Income 4. Purchase supplies for cash. Supplies Cash 5. Issued a check to pay a creditor on account. Accounts Payable Cash 6. Collected payment from credit customer. Cash Accounts Receivable 7. Issued checks to pay employees their monthly salaries. Salaries Expense Cash 8. Performed services for cash. Accounts Receivable Fees Income 9. Received cash for damaged supplies returned. Cash Supplies 10. Issued a check to pay the telephone bill. Identify which control activity is violated in each of the following situations, and explain how the situation creates an opportunity for fraud or inappropriate accounting practices.1. Once a month, the sales department sends sales invoices to the accounting department to be recorded.2. Leah Hutcherson orders merchandise for Rice Lake Company; she also receives merchandise and authorizes payment for merchandise.3. Several clerks at Great Foods use the same cash register drawer 1. Primero, vamos a visitar el museo. Vamos a visitar _____. 2. Vemos el arte. vemos _____. 3. Entonces, comemos unos sandwiches. Entonces _____, comemos. 4. Luego, compramos regalos. Luego_____, compramos. 5. Despus, hay que leer los correos electrnicos. Despus, hay que leer _____. 6. Por fin, regresamos al hotel para ver la televisin. Por fin, regresamos al hotel para ver _____. list 3 things natural barriers china has How did you integrate information from the podcasts and the news article to build your understanding of peoples experiences with race and ethnicity? Why is it important to hear peoples personal experiences with race and ethnicity?R restateA Answer the questionC Cite textE ExplainI integrate information from the podcasts and the news article to build my understanding of peoples experiences with race and ethnicity by ; It's also important to hear peoples personal experiences with race and ethnicity because ;-I have to use the R.A.C.E. method to answer these questions. why kind of culture was in indianisation? Denise runs a 10 kilometer race (6.2 miles). Her average time per mile is shown. if y=1/3 when x=1/2 find y when x=1/4 Select the correct answer.What is the value oflog,OA.1B.2O c.3OD. 27Plz I need help I'm doing my test right now!!!! what is a independent and dependent variable THANK YALL FOR YALLS HELP CAN yall answer this 5x3x4x5= and how do you give someone a brainiest A few boats were traveling upstream and downstream. A satellite recorded the movements of several boats. A motor boat traveled -3.4 miles for every hour in 0.75 hours. How much progress? why we should elevated bed to waist level during bed making A 20 gallon tank is 3/4 full. How many gallons are in the tank? is this a function or not channged all sentences to passivesomebody should have cleaned the room. A student is helping his neighbor move a new dishwasher into their house. The house has three steps on the front porch that cause the porch to be 2 meters above the ground. Which method requires the least amount of force to get the dishwasher from the ground to the porch? ogan Products computes its predetermined overhead rate annually on the basis of direct labor-hours. At the beginning of the year, it estimated that 40,000 direct labor-hours would be required for the period's estimated level of production. The company also estimated $466,000 of fixed manufacturing overhead expenses for the coming period and variable manufacturing overhead of $3.00 per direct labor-hour. Logan's actual manufacturing overhead for the year was $713,400 and its actual total direct labor was 41,000 hours.Required:Compute the company's pre-determined overhead rate for the year.