Question 1

What number corresponds to F0.95,4,8?

Accepted Answer

A)  6.040 
B)  3.840 
C)  0.260 
D)  0.166 
A)  6.040 
B)  3.840 
C)  0.260 
D)  0.166

Question 2

We define   as the value of the F with v1 and v2 degrees of freedom such that the area to its right under the F curve is A, while   is defined as the value such that the area to its left is A.

Accepted Answer

A) True 
 B)False

Question 3

IT Graduates Salary
The recent average starting salary for new college graduates in IT systems is $47,500.Assume salaries are normally distributed with a standard deviation of $4,500.
-{IT Graduates Salary Narrative} What is the cutoff for the bottom 5% of the salaries?

Accepted Answer

The answer of IT Graduates Salary
The recent average starting salary...

Question 4

Checking Accounts
A bank has determined that the monthly balances of the checking accounts of its customers are normally distributed with an average balance of $1,200 and a standard deviation of $250.
-{Checking Accounts Narrative} What proportion of customers have monthly balances more than $1,125?

Accepted Answer

The answer of Checking Accounts
A bank has determined that the...

Question 5

Battery Life
A certain brand of batteries has a lifetime that has a normal distribution with a mean of 3,750 hours and a standard deviation of 300 hours.
-{Battery Life Narrative} What proportion of these batteries will last between 3,800 and 4,100 hours?

Accepted Answer

The answer of Battery Life
A certain brand of batteries has...

Question 6

The variance of a Student t distribution approaches zero as the degrees of freedom approaches infinity.

Accepted Answer

A) True 
 B)False

Question 7

A national standardized testing company can tell you your relative standing on an exam without divulging the mean or the standard deviation of the exam scores.

Accepted Answer

A) True 
 B)False

Question 8

A random variable X has a normal distribution with mean 132 and variance 36.If x = 120, its corresponding value of Z is 2.0.

Accepted Answer

A) True 
 B)False

Question 9

A c2 distribution with 5 degrees of freedom has a mean of ____________________ and a variance of ____________________.

Accepted Answer

Question 10

Given that Z is a standard normal random variable, the area to the left of a value z is expressed as

Accepted Answer

A)  P(Z $\ge$ z) 
B)  P(Z $\le$ z) 
C)  P(0 $\le$ Z$\le$ z) 
D)  P(Z $\ge$-z) 
A)  P(Z $\ge$ z) 
B)  P(Z $\le$ z) 
C)  P(0 $\le$ Z$\le$ z) 
D)  P(Z $\ge$-z)

Question 11

Suppose you have a c2 distribution with 20 degrees of freedom.
a.
Find the mean.
b.
Find the variance.
c.
Find the standard deviation.

Accepted Answer

Question 12

If   , then the number of degrees of freedom v is:

Accepted Answer

A)  5 
B)  6 
C)  7 
D)  8 
A)  5 
B)  6 
C)  7 
D)  8

Question 13

Phone Orders
The L.L.Bean catalog department that receives the majority of its orders by telephone conducted a study to determine how long customers were willing to wait on hold before ordering a product.The length of time was found to be a random variable best approximated by an exponential distribution with a mean equal to 3 minutes.
-{Phone Orders Narrative} What is the probability that a randomly selected caller is placed on hold for 3 to 6 minutes?

Accepted Answer

P(3 < X <

Question 14

If the random variable X is exponentially distributed, then the mean of X will be:

Accepted Answer

A)  greater than the median. 
B)  less than the median. 
C)  equal to the median. 
D)  Cannot tell; the answer depends on what $\lambda$ is. 
A)  greater than the median. 
B)  less than the median. 
C)  equal to the median. 
D)  Cannot tell; the answer depends on what $\lambda$ is.

Question 15

The value of a chi-squared distribution with 5 degrees of freedom such that the area to its left is 0.10 is 1.61.

Accepted Answer

A) True 
 B)False

What number corresponds to F_0.95,4,8?

We define as the value of the F with v₁ and v₂ degrees of freedom such that the area to its right under the F curve is A, while is defined as the value such that the area to its left is A.

IT Graduates Salary The recent average starting salary for new college graduates in IT systems is $47,500.Assume salaries are normally distributed with a standard deviation of $4,500. -{IT Graduates Salary Narrative} What is the cutoff for the bottom 5% of the salaries?

Checking Accounts A bank has determined that the monthly balances of the checking accounts of its customers are normally distributed with an average balance of $1,200 and a standard deviation of $250. -{Checking Accounts Narrative} What proportion of customers have monthly balances more than $1,125?

Battery Life A certain brand of batteries has a lifetime that has a normal distribution with a mean of 3,750 hours and a standard deviation of 300 hours. -{Battery Life Narrative} What proportion of these batteries will last between 3,800 and 4,100 hours?

The variance of a Student t distribution approaches zero as the degrees of freedom approaches infinity.

A national standardized testing company can tell you your relative standing on an exam without divulging the mean or the standard deviation of the exam scores.

A random variable X has a normal distribution with mean 132 and variance 36.If x = 120, its corresponding value of Z is 2.0.

A c² distribution with 5 degrees of freedom has a mean of and a variance of .

Given that Z is a standard normal random variable, the area to the left of a value z is expressed as

Suppose you have a c² distribution with 20 degrees of freedom. a. Find the mean. b. Find the variance. c. Find the standard deviation.

If , then the number of degrees of freedom v is:

If the random variable X is exponentially distributed, then the mean of X will be:

The value of a chi-squared distribution with 5 degrees of freedom such that the area to its left is 0.10 is 1.61.

What Is Statistics

Graphical Descriptive Techniques I

Graphical Descriptive Techniques II

Numerical Descriptive Techniques

Data Collection and Sampling

Probability

Random Variables and Discrete Probability Distributions

Sampling Distributions

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About a Population

Inference About Comparing Two Populations

Analysis of Variance

Chi-Squared Tests

Simple Linear Regression and Correlation

Multiple Regression

Filters

Exam 8: Continuous Probability Distributions

What number corresponds to F0.95,4,8?

We define as the value of the F with v1 and v2 degrees of freedom such that the area to its right under the F curve is A, while is defined as the value such that the area to its left is A.

IT Graduates Salary The recent average starting salary for new college graduates in IT systems is $47,500.Assume salaries are normally distributed with a standard deviation of $4,500. -{IT Graduates Salary Narrative} What is the cutoff for the bottom 5% of the salaries?

Battery Life A certain brand of batteries has a lifetime that has a normal distribution with a mean of 3,750 hours and a standard deviation of 300 hours. -{Battery Life Narrative} What proportion of these batteries will last between 3,800 and 4,100 hours?

The variance of a Student t distribution approaches zero as the degrees of freedom approaches infinity.

A national standardized testing company can tell you your relative standing on an exam without divulging the mean or the standard deviation of the exam scores.

A random variable X has a normal distribution with mean 132 and variance 36.If x = 120, its corresponding value of Z is 2.0.

A c2 distribution with 5 degrees of freedom has a mean of ____________________ and a variance of ____________________.

Given that Z is a standard normal random variable, the area to the left of a value z is expressed as

Suppose you have a c2 distribution with 20 degrees of freedom. a. Find the mean. b. Find the variance. c. Find the standard deviation.

If , then the number of degrees of freedom v is:

If the random variable X is exponentially distributed, then the mean of X will be:

The value of a chi-squared distribution with 5 degrees of freedom such that the area to its left is 0.10 is 1.61.

What Is Statistics

Graphical Descriptive Techniques I

Graphical Descriptive Techniques II

Numerical Descriptive Techniques

Data Collection and Sampling

Probability

Random Variables and Discrete Probability Distributions

Sampling Distributions

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About a Population

Inference About Comparing Two Populations

Analysis of Variance

Chi-Squared Tests

Simple Linear Regression and Correlation

Multiple Regression

Filters

What number corresponds to F_0.95,4,8?

We define as the value of the F with v₁ and v₂ degrees of freedom such that the area to its right under the F curve is A, while is defined as the value such that the area to its left is A.

A c² distribution with 5 degrees of freedom has a mean of and a variance of .

Suppose you have a c² distribution with 20 degrees of freedom. a. Find the mean. b. Find the variance. c. Find the standard deviation.