Question 1

To use the normal distribution to approximate the binomial distribution, we need ________ and ________ to be at least 5.

Accepted Answer

The answer of To use the normal distribution to approximate...

Question 2

The amount of time required for an oil and filter change on an automobile is normally distributed with a mean of 45 minutes and a standard deviation of 10 minutes. A random sample of 16 cars is selected. 90% of the sample means will be greater than what value?

Accepted Answer

The answer of The amount of time required for an...

Question 3

The sampling process begins by locating appropriate data sources called ________.

Accepted Answer

The answer of The sampling process begins by locating appropriate...

Question 4

If the amount of gasoline purchased per car at a large service station has a population mean of 15 gallons and a population standard deviation of 4 gallons and a random sample of 64 cars is selected, there is approximately a 95.44% chance that the sample mean will be between 14 and 16 gallons.

Accepted Answer

A) True 
 B)False

Question 5

The Central Limit Theorem is important in statistics because

Accepted Answer

A)  for a large n, it says the population is approximately normal. 
B)  for any population, it says the sampling distribution of the sample mean is approximately normal, regardless of the sample size. 
C)  for a large n, it says the sampling distribution of the sample mean is approximately normal, regardless of the shape of the population. 
D)  for a sample of any size, it says the sampling distribution of the sample mean is approximately normal. 
A)  for a large n, it says the population is approximately normal. 
B)  for any population, it says the sampling distribution of the sample mean is approximately normal, regardless of the sample size. 
C)  for a large n, it says the sampling distribution of the sample mean is approximately normal, regardless of the shape of the population. 
D)  for a sample of any size, it says the sampling distribution of the sample mean is approximately normal.

Question 6

TABLE 7-3
The mean selling price of new homes in a small town over a year was $115,000. The population standard deviation was $25,000. A random sample of 100 new home sales from this city was taken.
-Referring to Table 7-3, what is the probability that the sample mean selling price was between $114,000 and $116,000?

Accepted Answer

The answer of TABLE 7-3
The mean selling price of new...

Question 7

TABLE 7-2
The time spent studying by students in the week before final exams follows a normal distribution with a standard deviation of 8 hours. A random sample of 4 students was taken in order to estimate the mean study time for the population of all students.
-Referring to Table 7-2, what is the probability that the sample mean is more than 3 hours below the population mean?

Accepted Answer

The answer of TABLE 7-2
The time spent studying by students...

Question 8

The amount of tea leaves in a can from a particular production line is normally distributed with μ = 110 grams and σ = 25 grams. A sample of 25 cans is to be selected. What is the probability that the sample mean will be less than 100 grams?

Accepted Answer

The answer of The amount of tea leaves in a...

Question 9

Which of the following statements about the sampling distribution of the sample mean is incorrect?

Accepted Answer

A)  The sampling distribution of the sample mean is approximately normal whenever the sample size is sufficiently large (n ≥ 30). 
B)  The sampling distribution of the sample mean is generated by repeatedly taking samples of size n and computing the sample means. 
C)  The mean of the sampling distribution of the sample mean is equal to μ. 
D)  The standard deviation of the sampling distribution of the sample mean is equal to σ. 
A)  The sampling distribution of the sample mean is approximately normal whenever the sample size is sufficiently large (n ≥ 30). 
B)  The sampling distribution of the sample mean is generated by repeatedly taking samples of size n and computing the sample means. 
C)  The mean of the sampling distribution of the sample mean is equal to μ. 
D)  The standard deviation of the sampling distribution of the sample mean is equal to σ.

Question 10

A population frame for a survey contains a listing of 72,345 names. Using a table of random numbers, how many digits will the code numbers for each member of your population contain?

Accepted Answer

A)  3 
B)  4 
C)  5 
D)  6 
A)  3 
B)  4 
C)  5 
D)  6

Question 11

In a business statistics class, students sit randomly without particular preferences. A sample is selected by including everybody who sits in the first row. This is an example of a cluster sample.

Accepted Answer

A) True 
 B)False

Question 12

For sample sizes greater than 30, the sampling distribution of the mean will be approximately normally distributed

Accepted Answer

A)  regardless of the shape of the population. 
B)  only if the shape of the population is symmetrical. 
C)  only if the standard deviation of the samples are known. 
D)  only if the population is normally distributed. 
A)  regardless of the shape of the population. 
B)  only if the shape of the population is symmetrical. 
C)  only if the standard deviation of the samples are known. 
D)  only if the population is normally distributed.

Question 13

Major league baseball salaries averaged $3.26 million with a standard deviation of $1.2 million in a recent year. Suppose a sample of 100 major league players was taken. Find the approximate probability that the mean salary of the 100 players exceeded $3.5 million.

Accepted Answer

A)  approximately 0 
B)  0.0228 
C)  0.9772 
D)  approximately 1 
A)  approximately 0 
B)  0.0228 
C)  0.9772 
D)  approximately 1

Question 14

Which of the following is NOT a reason for the need for sampling?

Accepted Answer

A)  It is usually too costly to study the whole population. 
B)  It is usually too time consuming to look at the whole population. 
C)  It is sometimes destructive to observe the entire population. 
D)  It is always more informative by investigating a sample than the entire population. 
A)  It is usually too costly to study the whole population. 
B)  It is usually too time consuming to look at the whole population. 
C)  It is sometimes destructive to observe the entire population. 
D)  It is always more informative by investigating a sample than the entire population.

Question 15

Systematic samples are less efficient than a stratified sample.

Accepted Answer

A) True 
 B)False

Question 16

For air travelers, one of the biggest complaints is of the waiting time between when the airplane taxis away from the terminal until the flight takes off. This waiting time is known to have a right-skewed distribution with a mean of 10 minutes and a standard deviation of 8 minutes. Suppose 100 flights have been randomly sampled. Describe the sampling distribution of the mean waiting time between when the airplane taxis away from the terminal until the flight takes off for these 100 flights.

Accepted Answer

A)  Distribution is right-skewed with mean = 10 minutes and standard error = 0.8 minutes. 
B)  Distribution is right-skewed with mean = 10 minutes and standard error = 8 minutes. 
C)  Distribution is approximately normal with mean = 10 minutes and standard error = 0.8 minutes. 
D)  Distribution is approximately normal with mean = 10 minutes and standard error = 8 minutes. 
A)  Distribution is right-skewed with mean = 10 minutes and standard error = 0.8 minutes. 
B)  Distribution is right-skewed with mean = 10 minutes and standard error = 8 minutes. 
C)  Distribution is approximately normal with mean = 10 minutes and standard error = 0.8 minutes. 
D)  Distribution is approximately normal with mean = 10 minutes and standard error = 8 minutes.

Question 17

If the amount of gasoline purchased per car at a large service station has a population mean of 15 gallons and a population standard deviation of 4 gallons and a random sample of 4 cars is selected, there is approximately a 68.26% chance that the sample mean will be between 13 and 17 gallons.

Accepted Answer

A) True 
 B)False

Question 18

As a population becomes large, it is usually better to obtain statistical information from the entire population.

Accepted Answer

A) True 
 B)False

Question 19

The amount of bleach a machine pours into bottles has a mean of 36 oz. with a standard deviation of 0.15 oz. Suppose we take a random sample of 36 bottles filled by this machine. The sampling distribution of the sample mean has a mean of 36 oz.

Accepted Answer

A) True 
 B)False

Question 20

The amount of time required for an oil and filter change on an automobile is normally distributed with a mean of 45 minutes and a standard deviation of 10 minutes. A random sample of 16 cars is selected. What is the standard error of the mean?

Accepted Answer

The answer of The amount of time required for an...

To use the normal distribution to approximate the binomial distribution, we need and to be at least 5.

The amount of time required for an oil and filter change on an automobile is normally distributed with a mean of 45 minutes and a standard deviation of 10 minutes. A random sample of 16 cars is selected. 90% of the sample means will be greater than what value?

The sampling process begins by locating appropriate data sources called ________.

If the amount of gasoline purchased per car at a large service station has a population mean of 15 gallons and a population standard deviation of 4 gallons and a random sample of 64 cars is selected, there is approximately a 95.44% chance that the sample mean will be between 14 and 16 gallons.

The Central Limit Theorem is important in statistics because

The amount of tea leaves in a can from a particular production line is normally distributed with μ = 110 grams and σ = 25 grams. A sample of 25 cans is to be selected. What is the probability that the sample mean will be less than 100 grams?

Which of the following statements about the sampling distribution of the sample mean is incorrect?

A population frame for a survey contains a listing of 72,345 names. Using a table of random numbers, how many digits will the code numbers for each member of your population contain?

In a business statistics class, students sit randomly without particular preferences. A sample is selected by including everybody who sits in the first row. This is an example of a cluster sample.

For sample sizes greater than 30, the sampling distribution of the mean will be approximately normally distributed

Major league baseball salaries averaged $3.26 million with a standard deviation of $1.2 million in a recent year. Suppose a sample of 100 major league players was taken. Find the approximate probability that the mean salary of the 100 players exceeded $3.5 million.

Which of the following is NOT a reason for the need for sampling?

Systematic samples are less efficient than a stratified sample.

If the amount of gasoline purchased per car at a large service station has a population mean of 15 gallons and a population standard deviation of 4 gallons and a random sample of 4 cars is selected, there is approximately a 68.26% chance that the sample mean will be between 13 and 17 gallons.

As a population becomes large, it is usually better to obtain statistical information from the entire population.

The amount of bleach a machine pours into bottles has a mean of 36 oz. with a standard deviation of 0.15 oz. Suppose we take a random sample of 36 bottles filled by this machine. The sampling distribution of the sample mean has a mean of 36 oz.

The amount of time required for an oil and filter change on an automobile is normally distributed with a mean of 45 minutes and a standard deviation of 10 minutes. A random sample of 16 cars is selected. What is the standard error of the mean?

Introduction

Organizing and Visualizing Data

Numerical Descriptive Measures

Basic Probability

Discrete Probability Distributions

The Normal Distribution

Confidence Interval Estimation

Fundamentals of Hypothesis Testing: One-Sample Tests

Two-Sample Tests and One-Way ANOVA

Chi-Square Tests

Simple Linear Regression

Introduction to Multiple Regression

Statistical Applications in Quality Management

Filters

Exam 7: Sampling and Sampling Distributions

To use the normal distribution to approximate the binomial distribution, we need ________ and ________ to be at least 5.

The amount of time required for an oil and filter change on an automobile is normally distributed with a mean of 45 minutes and a standard deviation of 10 minutes. A random sample of 16 cars is selected. 90% of the sample means will be greater than what value?

The sampling process begins by locating appropriate data sources called ________.

If the amount of gasoline purchased per car at a large service station has a population mean of 15 gallons and a population standard deviation of 4 gallons and a random sample of 64 cars is selected, there is approximately a 95.44% chance that the sample mean will be between 14 and 16 gallons.

The Central Limit Theorem is important in statistics because

The amount of tea leaves in a can from a particular production line is normally distributed with μ = 110 grams and σ = 25 grams. A sample of 25 cans is to be selected. What is the probability that the sample mean will be less than 100 grams?

Which of the following statements about the sampling distribution of the sample mean is incorrect?

A population frame for a survey contains a listing of 72,345 names. Using a table of random numbers, how many digits will the code numbers for each member of your population contain?

In a business statistics class, students sit randomly without particular preferences. A sample is selected by including everybody who sits in the first row. This is an example of a cluster sample.

For sample sizes greater than 30, the sampling distribution of the mean will be approximately normally distributed

Major league baseball salaries averaged $3.26 million with a standard deviation of $1.2 million in a recent year. Suppose a sample of 100 major league players was taken. Find the approximate probability that the mean salary of the 100 players exceeded $3.5 million.

Which of the following is NOT a reason for the need for sampling?

Systematic samples are less efficient than a stratified sample.

If the amount of gasoline purchased per car at a large service station has a population mean of 15 gallons and a population standard deviation of 4 gallons and a random sample of 4 cars is selected, there is approximately a 68.26% chance that the sample mean will be between 13 and 17 gallons.

As a population becomes large, it is usually better to obtain statistical information from the entire population.

The amount of bleach a machine pours into bottles has a mean of 36 oz. with a standard deviation of 0.15 oz. Suppose we take a random sample of 36 bottles filled by this machine. The sampling distribution of the sample mean has a mean of 36 oz.

The amount of time required for an oil and filter change on an automobile is normally distributed with a mean of 45 minutes and a standard deviation of 10 minutes. A random sample of 16 cars is selected. What is the standard error of the mean?

Introduction

Organizing and Visualizing Data

Numerical Descriptive Measures

Basic Probability

Discrete Probability Distributions

The Normal Distribution

Confidence Interval Estimation

Fundamentals of Hypothesis Testing: One-Sample Tests

Two-Sample Tests and One-Way ANOVA

Chi-Square Tests

Simple Linear Regression

Introduction to Multiple Regression

Statistical Applications in Quality Management

Filters

To use the normal distribution to approximate the binomial distribution, we need and to be at least 5.