Question 1

The number of defectives in 10 different samples of 100 observations each is the following: 1,2,1,0,2,3,1,4,2,1.What is the estimate of the population proportion of defectives?

Accepted Answer

A)  .017
B)  .17
C)  .016
D)  .16E) A) and B)
F) C) and D)

Question 2

A random sample of size 1,000 is taken from a population where p = .20.What is  ?p^{?} _{ \hat { p }} ?p^​​ 
?

Accepted Answer

A)  .006
B)  .20
C)  .02
D)  .16 E) B) and D)
F) A) and D)

Question 3

According to a hospital administrator,historical records over the past 10 years have shown that 20 percent of the major surgery patients are dissatisfied with after-surgery care in the hospital.A scientific poll based on 400 hospital patients has just been conducted.What is the probability that at least 70 patients will not be satisfied with the after-surgery care?

Accepted Answer

A)  89.44%
B)  39.44%
C)  10.56%
D)  78.88%
E)  84.49%F) C) and D)
G) A) and B)

Question 4

A random sample of size 36 is taken from a population with mean 50 and standard deviation 5.Find  P(Xˉ<51.5) \mathrm { P } ( \bar { X } < 51.5 ) P(Xˉ<51.5)

Accepted Answer

A)  .9641
B)  .0359
C)  .1389
D)  .9999 E) B) and C)
F) B) and D)

Question 5

The population of lengths of aluminum-coated steel sheets is normally distributed with a mean of 30.05 inches and a standard deviation of 0.3 inches.What is the probability that the average length of a steel sheet from a sample of 9 units is more than 29.95 inches long?

Accepted Answer

A)  .8413
B)  .6293
C)  .3707
D)  .1587E) All of the above
F) None of the above

Question 6

As the sample size ______________,the variation of the sampling distribution of  Xˉ\bar { X }Xˉ 
___________.

Accepted Answer

A)  Decreases,decreases
B)  Increases,remains the same
C)  Decreases,remains the same
D)  Increases,decreases
E)  None of these F) D) and E)
G) C) and D)

Question 7

The diameter of small Nerf balls manufactured at a factory in China is expected to be approximately normally distributed with a mean of 5.2 inches and a standard deviation of .08 inches.Suppose a random sample of 20 balls is selected.Calculate the standard deviation of the sampling distribution of the sample mean.

Accepted Answer

A)  5.2
B)  0.018
C)  0.08
D)  0.063E) All of the above
F) A) and B)

Question 8

According to the Central Limit Theorem,if a sample size is at least _____,then for most sampled populations,we can conclude that the sample means are approximately normal.

Accepted Answer

A)  25
B)  20
C)  30
D)  50E) A) and B)
F) A) and C)

Question 9

If a population is known to be normally distributed,then it follows that the sample mean must equal the population mean.

Accepted Answer

A) True 
 B)False

Question 10

____________ says that if the sample size is sufficiently large,then the sample means are approximately normally distributed.

Accepted Answer

A)  Cluster sampling
B)  Sampling error
C)  Sampling distribution of the mean
D)  The Central Limit TheoremE) None of the above
F) A) and B)

Question 11

Consider a sampling distribution formed based on n = 3.The standard deviation of the population of all sample means  σXˉ\sigma _ { \bar { X } }σXˉ​ 
Is ______________ less than the standard deviation of the population of individual measurements ?.

Accepted Answer

A)  Always
B)  Sometimes
C)  Never D) None of the above
E) All of the above

Question 12

It has been reported that the average time to download the home page from a government website was 0.9 seconds.Suppose that the download times were normally distributed with a standard deviation of 0.3 seconds.If random samples of 36 download times are selected,calculate the standard deviation of the sampling distribution of the sample mean.

Accepted Answer

A)  0.3
B)  0.15
C)  0.9
D)  0.05E) All of the above
F) B) and D)

Question 13

The mean of the sampling distribution of the sample proportion is equal to _____ when the sample size is sufficiently large.

Accepted Answer

A)  μ
B)  p
C)  p × n
D)  (1 - p) E) C) and D)
F) B) and C)

Question 14

The Central Limit Theorem states that as the sample size increases,the distribution of the sample ____________ approaches the normal distribution.

Accepted Answer

A)  Medians
B)  Means
C)  Standard deviations
D)  VariancesE) A) and B)
F) A) and C)

Question 15

As the sample size increases,the standard deviation of the sampling distribution increases.

Accepted Answer

A) True 
 B)False

Question 16

The quantity √(N - n)(N - 1)is called the finite population multiplier.

Accepted Answer

A) True 
 B)False

Question 17

A low response rate has no effect on the validity of a survey's findings.

Accepted Answer

A) True 
 B)False

Question 18

It has been reported that the average time to download the home page from a government website was 0.9 seconds.Suppose that the download times were normally distributed with a standard deviation of 0.3 seconds.If random samples of 36 download times are selected,what is the probability that the sample mean will be less than 0.84 seconds?

Accepted Answer

A)  .1151
B)  .4522
C)  .8849
D)  .5478E) B) and C)
F) C) and D)

Question 19

Packages of sugar bags for Sweeter Sugar Inc.have an average weight of 16 ounces and a standard deviation of 0.2 ounces.The weights of the sugar packages are normally distributed.What is the probability that 16 randomly selected packages will have a weight in excess of 16.075 ounces?

Accepted Answer

A)  .0500
B)  .3520
C)  .9332
D)  .0668E) A) and B)
F) A) and C)

Question 20

A random sample of size 1,000 is taken from a population where p = .20.What is  (σp˙) \left( \sigma _ { \dot { p } } \right) (σp˙​​)  
?

Accepted Answer

A)  .0051
B)  .03162
C)  .01414
D)  .01265 E) None of the above
F) A) and D)

Exam 7: Sampling and Sampling Distributions

According to the Central Limit Theorem,if a sample size is at least _____,then for most sampled populations,we can conclude that the sample means are approximately normal.

Correct Answer
verified

If a population is known to be normally distributed,then it follows that the sample mean must equal the population mean.

Correct Answer
verified

A random sample of size 1,000 is taken from a population where p = .20.What is ${?} _{ \hat { p }}$ ?

Correct Answer
verified

As the sample size increases,the standard deviation of the sampling distribution increases.

Correct Answer
verified

Correct Answer
verified

A random sample of size 36 is taken from a population with mean 50 and standard deviation 5.Find $\mathrm { P } ( \bar { X } < 51.5 )$

Correct Answer
verified

The number of defectives in 10 different samples of 100 observations each is the following: 1,2,1,0,2,3,1,4,2,1.What is the estimate of the population proportion of defectives?

Correct Answer
verified

Consider a sampling distribution formed based on n = 3.The standard deviation of the population of all sample means $\sigma _ { \bar { X } }$ Is ______________ less than the standard deviation of the population of individual measurements ?.

Correct Answer
verified

The population of lengths of aluminum-coated steel sheets is normally distributed with a mean of 30.05 inches and a standard deviation of 0.3 inches.What is the probability that the average length of a steel sheet from a sample of 9 units is more than 29.95 inches long?

Correct Answer
verified

The quantity √(N - n)(N - 1)is called the finite population multiplier.

Correct Answer
verified

The mean of the sampling distribution of the sample proportion is equal to _____ when the sample size is sufficiently large.

Correct Answer
verified

The Central Limit Theorem states that as the sample size increases,the distribution of the sample ____________ approaches the normal distribution.

Correct Answer
verified

Correct Answer
verified

____________ says that if the sample size is sufficiently large,then the sample means are approximately normally distributed.

Correct Answer
verified

As the sample size ____,the variation of the sampling distribution of $\bar { X }$ _.

Correct Answer
verified

A low response rate has no effect on the validity of a survey's findings.

Correct Answer
verified

A random sample of size 1,000 is taken from a population where p = .20.What is $\left( \sigma _ { \dot { p } } \right)$ ?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Packages of sugar bags for Sweeter Sugar Inc.have an average weight of 16 ounces and a standard deviation of 0.2 ounces.The weights of the sugar packages are normally distributed.What is the probability that 16 randomly selected packages will have a weight in excess of 16.075 ounces?

Correct Answer
verified

Exam 7: Sampling and Sampling Distributions

According to the Central Limit Theorem,if a sample size is at least _____,then for most sampled populations,we can conclude that the sample means are approximately normal.

Correct AnswerverifiedShow Answer

If a population is known to be normally distributed,then it follows that the sample mean must equal the population mean.

Correct AnswerverifiedShow Answer

A random sample of size 1,000 is taken from a population where p = .20.What is ?p^{?} _{ \hat { p }} ?p^​​ ?

Correct AnswerverifiedShow Answer

As the sample size increases,the standard deviation of the sampling distribution increases.

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

A random sample of size 36 is taken from a population with mean 50 and standard deviation 5.Find P(Xˉ<51.5) \mathrm { P } ( \bar { X } < 51.5 ) P(Xˉ<51.5)

Correct AnswerverifiedShow Answer

The number of defectives in 10 different samples of 100 observations each is the following: 1,2,1,0,2,3,1,4,2,1.What is the estimate of the population proportion of defectives?

Correct AnswerverifiedShow Answer

Consider a sampling distribution formed based on n = 3.The standard deviation of the population of all sample means σXˉ\sigma _ { \bar { X } }σXˉ​ Is ______________ less than the standard deviation of the population of individual measurements ?.

Correct AnswerverifiedShow Answer

The population of lengths of aluminum-coated steel sheets is normally distributed with a mean of 30.05 inches and a standard deviation of 0.3 inches.What is the probability that the average length of a steel sheet from a sample of 9 units is more than 29.95 inches long?

Correct AnswerverifiedShow Answer

The quantity √(N - n)(N - 1)is called the finite population multiplier.

Correct AnswerverifiedShow Answer

The mean of the sampling distribution of the sample proportion is equal to _____ when the sample size is sufficiently large.

Correct AnswerverifiedShow Answer

The Central Limit Theorem states that as the sample size increases,the distribution of the sample ____________ approaches the normal distribution.

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

____________ says that if the sample size is sufficiently large,then the sample means are approximately normally distributed.

Correct AnswerverifiedShow Answer

As the sample size ______________,the variation of the sampling distribution of Xˉ\bar { X }Xˉ ___________.

Correct AnswerverifiedShow Answer

A low response rate has no effect on the validity of a survey's findings.

Correct AnswerverifiedShow Answer

A random sample of size 1,000 is taken from a population where p = .20.What is (σp˙) \left( \sigma _ { \dot { p } } \right) (σp˙​​) ?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Packages of sugar bags for Sweeter Sugar Inc.have an average weight of 16 ounces and a standard deviation of 0.2 ounces.The weights of the sugar packages are normally distributed.What is the probability that 16 randomly selected packages will have a weight in excess of 16.075 ounces?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

A random sample of size 1,000 is taken from a population where p = .20.What is ${?} _{ \hat { p }}$ ?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

A random sample of size 36 is taken from a population with mean 50 and standard deviation 5.Find $\mathrm { P } ( \bar { X } < 51.5 )$

Correct Answer
verified

Correct Answer
verified

Consider a sampling distribution formed based on n = 3.The standard deviation of the population of all sample means $\sigma _ { \bar { X } }$ Is ______________ less than the standard deviation of the population of individual measurements ?.

Correct Answer
verified

Correct Answer
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Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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As the sample size ____,the variation of the sampling distribution of $\bar { X }$ _.

Correct Answer
verified

Correct Answer
verified

A random sample of size 1,000 is taken from a population where p = .20.What is $\left( \sigma _ { \dot { p } } \right)$ ?

Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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