Question 1

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

Question 2

Instruction 7.1
Times spent studying by students in the week before final exams follow 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 Instruction 7.1,what is the probability that the sample mean differs from the population mean by less than 2 hours?

Accepted Answer

0.3829 usi

Question 3

At a computer manufacturing company,the actual size of computer chips is normally distributed with a mean of 1 cm and a standard deviation of 0.1 cm.A random sample of 12 computer chips is taken.
-What is the probability that the sample mean will be below 0.95 cm?

Accepted Answer

0.0416 usi

Question 4

Suppose μ = 50 and σ2 = 100 for a population.In a sample where n = 100 is randomly taken,90% of all possible sample means will fall between 49 and 51.

Accepted Answer

A) True 
 B)False

Question 5

The Central Limit Theorem ensures that the sampling distribution of the sample mean approaches normal as the sample size increases.

Accepted Answer

A) True 
 B)False

Question 6

A study at a university in New South Wales reveals that,historically,45% of their students are minority students.If random samples of size 75 are selected,80% of the samples will have less than _________ % of minority students.

Accepted Answer

The answer of A study at a university in New...

Question 7

Suppose μ = 50 and σ = 10 for a population.In a sample where n = 100 is randomly taken,95% of all possible sample means will fall between 48.04 and 51.96.

Accepted Answer

A) True 
 B)False

Question 8

One key requirement of sampling in inferential statistics is that

Accepted Answer

A)  the sample size must be proportional to the population size. 
B)  the members of the sample must be selected systematically. 
C)  the sample size must be determined in advance. 
D)  the sample must include representation of all major groups within the population. 
A)  the sample size must be proportional to the population size. 
B)  the members of the sample must be selected systematically. 
C)  the sample size must be determined in advance. 
D)  the sample must include representation of all major groups within the population.

Question 9

A study at a university in New South Wales reveals that,historically,45% of their students are minority students.If a random sample of size 75 is selected,the probability is _________  that more than half of the students in the sample will be minority students.

Accepted Answer

0.1920 usi

Question 10

Instruction 7.4
According to a survey, only 15% of customers who visited the web site of a major retail store made a purchase. Random samples of size 50 are selected.
-Referring to Instruction 7.4,90% of the samples will have less than what percentage of customers who will make a purchase after visiting the web site?

Accepted Answer

The answer of Instruction 7.4
According to a survey, only 15%...

Question 11

The standard error of the population proportion will become larger

Accepted Answer

A)  as population proportion approaches 0. 
B)  as population proportion approaches 0.50. 
C)  as the sample size increases. 
D)  as population proportion approaches 1.00. 
A)  as population proportion approaches 0. 
B)  as population proportion approaches 0.50. 
C)  as the sample size increases. 
D)  as population proportion approaches 1.00.

Question 12

Instruction 7.6
Online customer service is a key element to successful online retailing. According to a marketing survey, 37.5% of online customers take advantage of the online customer service. Random samples of 200 customers are selected.
-Referring to Instruction 7.6,the standard error of all possible sample proportions is _________ .

Accepted Answer

The answer of Instruction 7.6
Online customer service is a key...

Question 13

If the amount of petrol purchased per car at a large petrol station has a population mean of $15 and a population standard deviation of $4 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.

Accepted Answer

A) True 
 B)False

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

At a computer manufacturing company,the actual size of computer chips is normally distributed with a mean of 1 cm and a standard deviation of 0.1 cm.A random sample of 12 computer chips is taken. -What is the probability that the sample mean will be below 0.95 cm?

Suppose μ = 50 and σ²= 100 for a population.In a sample where n = 100 is randomly taken,90% of all possible sample means will fall between 49 and 51.

The Central Limit Theorem ensures that the sampling distribution of the sample mean approaches normal as the sample size increases.

A study at a university in New South Wales reveals that,historically,45% of their students are minority students.If random samples of size 75 are selected,80% of the samples will have less than _________ % of minority students.

Suppose μ = 50 and σ= 10 for a population.In a sample where n = 100 is randomly taken,95% of all possible sample means will fall between 48.04 and 51.96.

One key requirement of sampling in inferential statistics is that

A study at a university in New South Wales reveals that,historically,45% of their students are minority students.If a random sample of size 75 is selected,the probability is _________ that more than half of the students in the sample will be minority students.

The standard error of the population proportion will become larger

If the amount of petrol purchased per car at a large petrol station has a population mean of $15 and a population standard deviation of $4 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.

Defining and Collecting Data

Organising and Visualising Data

Numerical Descriptive Measures

Basic Probability

Some Important Discrete Probability Distributions

The Normal Distribution and Other Continuous Distributions

Confidence Interval Estimation

Fundamentals of Hypothesis Testing: One-Sample Tests

Hypothesis Testing: Two-Sample Tests

Analysis of Variance

Simple Linear Regression

Introduction to Multiple Regression

Time-Series Forecasting and Index Numbers

Chi-Square Tests

Multiple Regression Model Building

Decision Making

Statistical Applications in Quality Management

Further Non-Parametric Tests

Filters

Exam 7: Sampling Distributions

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

At a computer manufacturing company,the actual size of computer chips is normally distributed with a mean of 1 cm and a standard deviation of 0.1 cm.A random sample of 12 computer chips is taken. -What is the probability that the sample mean will be below 0.95 cm?

Suppose μ = 50 and σ2 = 100 for a population.In a sample where n = 100 is randomly taken,90% of all possible sample means will fall between 49 and 51.

The Central Limit Theorem ensures that the sampling distribution of the sample mean approaches normal as the sample size increases.

A study at a university in New South Wales reveals that,historically,45% of their students are minority students.If random samples of size 75 are selected,80% of the samples will have less than _________ % of minority students.

Suppose μ = 50 and σ = 10 for a population.In a sample where n = 100 is randomly taken,95% of all possible sample means will fall between 48.04 and 51.96.

One key requirement of sampling in inferential statistics is that

A study at a university in New South Wales reveals that,historically,45% of their students are minority students.If a random sample of size 75 is selected,the probability is _________ that more than half of the students in the sample will be minority students.

The standard error of the population proportion will become larger

If the amount of petrol purchased per car at a large petrol station has a population mean of $15 and a population standard deviation of $4 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.

Defining and Collecting Data

Organising and Visualising Data

Numerical Descriptive Measures

Basic Probability

Some Important Discrete Probability Distributions

The Normal Distribution and Other Continuous Distributions

Confidence Interval Estimation

Fundamentals of Hypothesis Testing: One-Sample Tests

Hypothesis Testing: Two-Sample Tests

Analysis of Variance

Simple Linear Regression

Introduction to Multiple Regression

Time-Series Forecasting and Index Numbers

Chi-Square Tests

Multiple Regression Model Building

Decision Making

Statistical Applications in Quality Management

Further Non-Parametric Tests

Filters

Suppose μ = 50 and σ²= 100 for a population.In a sample where n = 100 is randomly taken,90% of all possible sample means will fall between 49 and 51.

Suppose μ = 50 and σ= 10 for a population.In a sample where n = 100 is randomly taken,95% of all possible sample means will fall between 48.04 and 51.96.