Question 1

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

Accepted Answer

A) .9641 
B) .0359 
C) .1389 
D) .9999 
A) .9641 
B) .0359 
C) .1389 
D) .9999

Question 2

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) 0.05 
A) 0.3 
B) 0.15 
C) 0.9 
D) 0.05

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

Question 4

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) 0.063 
A) 5.2 
B) 0.018 
C) 0.08 
D) 0.063

Question 5

____________ 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 Theorem 
A) Cluster sampling 
B) Sampling error 
C) Sampling distribution of the mean 
D) The Central Limit Theorem

Question 6

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) .1587 
A) .8413 
B) .6293 
C) .3707 
D) .1587

Question 7

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) Variances 
A) Medians 
B) Means 
C) Standard deviations 
D) Variances

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) 50 
A) 25 
B) 20 
C) 30 
D) 50

Question 9

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

Accepted Answer

A) True 
 B)False

Question 10

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

Accepted Answer

A) .006 
B) .20 
C) .02 
D) .16 
A) .006 
B) .20 
C) .02 
D) .16

Question 11

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

Accepted Answer

A) True 
 B)False

Question 12

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

Accepted Answer

A) .0051 
B) .03162 
C) .01414 
D) .01265 
A) .0051 
B) .03162 
C) .01414 
D) .01265

Question 13

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 ?.

Accepted Answer

A) Always 
B) Sometimes 
C) Never 
A) Always 
B) Sometimes 
C) Never

Question 14

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 15

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) .0668 
A) .0500 
B) .3520 
C) .9332 
D) .0668

Question 16

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

Accepted Answer

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

Question 17

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) .5478 
A) .1151 
B) .4522 
C) .8849 
D) .5478

Question 18

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) 
A) μ 
B) p 
C) p × n 
D) (1 - p)

Question 19

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

Accepted Answer

A) True 
 B)False

Question 20

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) .16 
A) .017 
B) .17 
C) .016 
D) .16

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

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

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?

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

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.

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

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

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

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

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 ?.

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

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?

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

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

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

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?

An Introduction to Business Statistics

Descriptive Statistics: Tabular and Graphical Methods

Descriptive Statistics: Numerical Methods

Probability

Discrete Random Variables

Continuous Random Variables

Confidence Intervals

Hypothesis Testing

Comparing Two Means and Two Proportions

Filters

Exam 7: Sampling and Sampling Distributions

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)

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

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?

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

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.

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

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

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

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

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 ?.

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

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?

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

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

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

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?

An Introduction to Business Statistics

Descriptive Statistics: Tabular and Graphical Methods

Descriptive Statistics: Numerical Methods

Probability

Discrete Random Variables

Continuous Random Variables

Confidence Intervals

Hypothesis Testing

Comparing Two Means and Two Proportions

Filters

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

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

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

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 ?.

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