# OpenStax-CNX

You are here: Home » Content » Collaborative Statistics » Practice Final Exam 2

### Lenses

What is a lens?

#### Definition of a lens

##### Lenses

A lens is a custom view of the content in the repository. You can think of it as a fancy kind of list that will let you see content through the eyes of organizations and people you trust.

##### What is in a lens?

Lens makers point to materials (modules and collections), creating a guide that includes their own comments and descriptive tags about the content.

##### Who can create a lens?

Any individual member, a community, or a respected organization.

##### What are tags?

Tags are descriptors added by lens makers to help label content, attaching a vocabulary that is meaningful in the context of the lens.

#### Endorsed by (What does "Endorsed by" mean?)

This content has been endorsed by the organizations listed. Click each link for a list of all content endorsed by the organization.
• College Open Textbooks

This collection is included inLens: Community College Open Textbook Collaborative
By: CC Open Textbook Collaborative

"Reviewer's Comments: 'I recommend this book. Overall, the chapters are very readable and the material presented is consistent and appropriate for the course. A wide range of exercises introduces […]"

Click the "College Open Textbooks" link to see all content they endorse.

Click the tag icon to display tags associated with this content.

• JVLA Endorsed

This collection is included inLens: Jesuit Virtual Learning Academy Endorsed Material

"This is a robust collection (textbook) approved by the College Board as a resource for the teaching of AP Statistics. "

Click the "JVLA Endorsed" link to see all content they endorse.

• WebAssign

This collection is included inLens: WebAssign The Independent Online Homework and Assessment Solution
By: WebAssign

"Online homework and assessment available from WebAssign."

Click the "WebAssign" link to see all content they endorse.

Click the tag icon to display tags associated with this content.

#### Affiliated with (What does "Affiliated with" mean?)

This content is either by members of the organizations listed or about topics related to the organizations listed. Click each link to see a list of all content affiliated with the organization.
• OrangeGrove

This collection is included inLens: Florida Orange Grove Textbooks
By: Florida Orange Grove

Click the "OrangeGrove" link to see all content affiliated with them.

Click the tag icon to display tags associated with this content.

• Bookshare

This collection is included inLens: Bookshare's Lens
By: Bookshare - A Benetech Initiative

"DAISY and BRF versions of this collection are available."

Click the "Bookshare" link to see all content affiliated with them.

• Featured Content

This collection is included inLens: Connexions Featured Content
By: Connexions

"Collaborative Statistics was written by two faculty members at De Anza College in Cupertino, California. This book is intended for introductory statistics courses being taken by students at two- […]"

Click the "Featured Content" link to see all content affiliated with them.

Click the tag icon to display tags associated with this content.

#### Also in these lenses

• statistics

This collection is included inLens: Statistics
By: Brylie Oxley

Click the "statistics" link to see all content selected in this lens.

Click the tag icon to display tags associated with this content.

• Lucy Van Pelt

This collection is included inLens: Lucy's Lens
By: Tahiya Marome

"Part of the Books featured on Community College Open Textbook Project"

Click the "Lucy Van Pelt" link to see all content selected in this lens.

Click the tag icon to display tags associated with this content.

• Educational Technology Lens

This collection is included inLens: Educational Technology
By: Steve Wilhite

Click the "Educational Technology Lens" link to see all content selected in this lens.

Click the tag icon to display tags associated with this content.

• Statistics

This collection is included inLens: Mathieu Plourde's Lens
By: Mathieu Plourde

Click the "Statistics" link to see all content selected in this lens.

• statf12

This collection is included inLens: Statistics Fall 2012
By: Alex Kolesnik

Click the "statf12" link to see all content selected in this lens.

• UTEP

This collection is included inLens: Amy Wagler's Lens
By: Amy Wagler

Click the "UTEP" link to see all content selected in this lens.

Click the tag icon to display tags associated with this content.

• Make Textbooks Affordable

This collection is included inLens: Make Textbooks Affordable
By: Nicole Allen

Click the "Make Textbooks Affordable" link to see all content selected in this lens.

• BUS204 Homework

This collection is included inLens: Saylor BUS 204 Homework
By: David Bourgeois

"Homework for Discrete Variables/Probability. "

Click the "BUS204 Homework" link to see all content selected in this lens.

Click the tag icon to display tags associated with this content.

• crowe

This collection is included in aLens by: Chris Rowe

Click the "crowe" link to see all content selected in this lens.

• Bio 502 at CSUDH

This collection is included inLens: Bio 502
By: Terrence McGlynn

"This is the course textbook for Biology 502 at CSU Dominguez Hills"

Click the "Bio 502 at CSUDH" link to see all content selected in this lens.

Click the tag icon to display tags associated with this content.

### Recently Viewed

This feature requires Javascript to be enabled.

### Tags

(What is a tag?)

These tags come from the endorsement, affiliation, and other lenses that include this content.

# Practice Final Exam 2

Summary: This module is a practice final for an associated elementary statistics textbook, Collaborative Statistics, available for Fall 2008.

## Exercise 1

A study was done to determine the proportion of teenagers that own a car. The population proportion of teenagers that own a car is the

• A. statistic
• B. parameter
• C. population
• D. variable

### Solution

B: parameter

The next two questions refer to the following data:

Table 1
value frequency
0 1
1 4
2 7
3 9
6 4

## Exercise 2

The box plot for the data is:

• A.
• B.
• C.
• D.

A

## Exercise 3

If 6 were added to each value of the data in the table, the 15th percentile of the new list of values is:

• A. 6
• B. 1
• C. 7
• D. 8

### Solution

C: 7

The next two questions refer to the following situation:

Suppose that the probability of a drought in any independent year is 20%. Out of those years in which a drought occurs, the probability of water rationing is 10%. However, in any year, the probability of water rationing is 5%.

## Exercise 4

What is the probability of both a drought and water rationing occurring?

• A. 0.05
• B. 0.01
• C. 0.02
• D. 0.30

C: 0.02

## Exercise 5

Which of the following is true?

• A. drought and water rationing are independent events
• B. drought and water rationing are mutually exclusive events
• C. none of the above

### Solution

C: none of the above

The next two questions refer to the following situation:

Suppose that a survey yielded the following data:

Table 2: Favorite Pie Type
gender apple pumpkin pecan
female 40 10 30
male 20 30 10

## Exercise 6

Suppose that one individual is randomly chosen. The probability that the person’s favorite pie is apple or the person is male is:

• A. 40 60 40 60
• B. 60 140 60 140
• C. 120 140 120 140
• D. 100 140 100 140

### Solution

D: 100 140 100 140

## Exercise 7

Suppose H o H o is: Favorite pie type and gender are independent.

The p-valuep-value is:

• A. ≈ 0
• B. 1
• C. 0.05
• D. cannot be determined

### Solution

A: ≈ 0

The next two questions refer to the following situation:

Let’s say that the probability that an adult watches the news at least once per week is 0.60. We randomly survey 14 people. Of interest is the number that watch the news at least once per week.

## Exercise 8

Which of the following statements is FALSE?

• A. X ~ B 14 0.60 X~B 14 0.60
• B. The values for xx are: { 1 ,2 ,3 ,... , 14 } { 1 ,2 ,3 ,... , 14 }
• C. μ = 8.4 μ=8.4
• D. P ( X = 5 ) = 0.0408P(X=5)=0.0408

### Solution

B: The values for xx are: { 1 ,2 ,3 ,... , 14 } { 1 ,2 ,3 ,... , 14 }

## Exercise 9

Find the probability that at least 6 adults watch the news.

• A. 6 14 6 14
• B. 0.8499
• C. 0.9417
• D. 0.6429

C: 0.9417

## Exercise 10

The following histogram is most likely to be a result of sampling from which distribution?

• A. Chi-Square with df = 6
• B. Exponential
• C. Uniform
• D. Binomial

### Solution

D: Binomial

The ages of campus day and evening students is known to be normally distributed. A sample of 6 campus day and evening students reported their ages (in years) as: { 18 ,35 ,27 ,45 , 20 , 20 } { 18 ,35 ,27 ,45 , 20 , 20 }

## Exercise 11

What is the error bound for the 90% confidence interval of the true average age?

• A. 11.2
• B. 22.3
• C. 17.5
• D. 8.7

D: 8.7

## Exercise 12

If a normally distributed random variable has µ = 0µ=0 and σ = 1σ=1 , then 97.5% of the population values lie above:

• A. -1.96
• B. 1.96
• C. 1
• D. -1

### Solution

A: -1.96

The next three questions refer to the following situation:

• A. 0.6321
• B. 0.5000
• C. 0.3714
• D. 1

A: 0.6321

## Exercise 14

How much money altogether would you expect next 5 customers to spend in one trip to the supermarket (in dollars)?

• A. 72
• B. 722 5 722 5
• C. 5184
• D. 360

D: 360

• A. 16
• B. 0.2
• C. 1
• D. 0.95

B: 0.2

## Exercise 23

If P ( Z < z α ) = 0P(Z< z α )=0. 1587 where Z Z~ N ( 0, 1 )N(0,1) , then αα is equal to:

• A. -1
• B. 0.1587
• C. 0.8413
• D. 1

A: -1

## Exercise 24

A professor tested 35 students to determine their entering skills. At the end of the term, after completing the course, the same test was administered to the same 35 students to study their improvement. This would be a test of:

• A. independent groups
• B. 2 proportions
• C. matched pairs, dependent groups
• D. exclusive groups

### Solution

C: matched pairs, dependent groups

## Exercise 25

A math exam was given to all the third grade children attending ABC School. Two random samples of scores were taken.

Table 3
n x¯x¯ s
Boys 55 82 5
Girls 60 86 7

Which of the following correctly describes the results of a hypothesis test of the claim, “There is a difference between the mean scores obtained by third grade girls and boys at the 5 % level of significance”?

• A. Do not reject H o H o . There is insufficient evidence to conclude that there is a difference in the mean scores.
• B. Do not reject H o H o . There is sufficient evidence to conclude that there is a difference in the mean scores.
• C. Reject H o H o . There is insufficient evidence to conclude that there is no difference in the mean scores.
• D. Reject H o H o . There is sufficient evidence to conclude that there is a difference in the mean scores.

### Solution

D: Reject H o H o . There is sufficient evidence to conclude that there is a difference in the mean scores.

## Exercise 26

In a survey of 80 males, 45 had played an organized sport growing up. Of the 70 females surveyed, 25 had played an organized sport growing up. We are interested in whether the proportion for males is higher than the proportion for females. The correct conclusion is:

• A. There is insufficient information to conclude that the proportion for males is the same as the proportion for females.
• B. There is insufficient information to conclude that the proportion for males is not the same as the proportion for females.
• C. There is sufficient evidence to conclude that the proportion for males is higher than the proportion for females.
• D. Not enough information to determine.

### Solution

C: There is sufficient evidence to conclude that the proportion for males is higher than the proportion for females.

## Exercise 27

Note: Chi-Square Test of a Single Variance; Not all classes cover this topic. From past experience, a statistics teacher has found that the average score on a midterm is 81 with a standard deviation of 5.2. This term, a class of 49 students had a standard deviation of 5 on the midterm. Do the data indicate that we should reject the teacher’s claim that the standard deviation is 5.2? Use α = 0.05 α=0.05.

• A. Yes
• B. No
• C. Not enough information given to solve the problem

B: No

## Exercise 28

Note: F Distribution Test of ANOVA; Not all classes cover this topic. Three loading machines are being compared. Ten samples were taken for each machine. Machine I took an average of 31 minutes to load packages with a standard deviation of 2 minutes. Machine II took an average of 28 minutes to load packages with a standard deviation of 1.5 minutes. Machine III took an average of 29 minutes to load packages with a standard deviation of 1 minute. Find the p-valuep-value when testing that the average loading times are the same.

• A. the p–valuep–value is close to 0
• B. p–valuep–value is close to 1
• C. Not enough information given to solve the problem

### Solution

B: p-value is close to 1.

The next three questions refer to the following situation:

A corporation has offices in different parts of the country. It has gathered the following information concerning the number of bathrooms and the number of employees at seven sites:

 Number of employees x Number of bathrooms y 650 730 810 900 102 107 1150 40 50 54 61 82 110 121

## Exercise 29

Is the correlation between the number of employees and the number of bathrooms significant?

• A. Yes
• B. No
• C. Not enough information to answer question

B: No

## Exercise 30

The linear regression equation is:

• A. y ̂ = 0.0094 79.96 x y ̂ =0.009479.96x
• B. y ̂ = 79.96 + 0.0094x y ̂ =79.96+0.0094x
• C. y ̂ = 79.96 - 0.0094x y ̂ =79.96-0.0094x
• D. y ̂ = 0.0094 + 79.96 x y ̂ =0.0094+79.96x

### Solution

C: y ̂ = 79.96 x - 0.0094 y ̂ =79.96x-0.0094

## Exercise 31

If a site has 1150 employees, approximately how many bathrooms should it have?

• A. 69
• B. 91
• C. 91,954
• D. We should not be estimating here.

### Solution

D: We should not be estimating here.

## Exercise 32

Note: Chi-Square Test of a Single Variance; Not all classes cover this topic. Suppose that a sample of size 10 was collected, with x¯ x = 4.4 and ss = 1.4 .

H o H o : σ 2 σ 2 = 1.6 vs. H a H a : σ 2 σ 2 ≠ 1.6. Which graph best describes the results of the test?

A

## Exercise 33

64 backpackers were asked the number of days their latest backpacking trip was. The number of days is given in the table below:

 # of days Frequency 1 2 3 4 5 6 7 8 5 9 6 12 7 10 5 10

Conduct an appropriate test to determine if the distribution is uniform.

• A. The p–valuep–value is > 0.10. There is insufficient information to conclude that the distribution is not uniform.
• B. The p–valuep–value is < 0.01. There is sufficient information to conclude the distribution is not uniform.
• C. The p–valuep–value is between 0.01 and 0.10, but without alpha (α) there is not enough information
• D. There is no such test that can be conducted.

### Solution

A: The p–valuep–value is > 0.10. There is insufficient information to conclude that the distribution is not uniform.

## Exercise 34

­Note: F Distribution test of One-Way ANOVA; Not all classes cover this topic. Which of the following statements is true when using one-way ANOVA?

• A. The populations from which the samples are selected have different distributions.
• B. The sample sizes are large.
• C. The test is to determine if the different groups have the same means.
• D. There is a correlation between the factors of the experiment.

### Solution

C: The test is to determine if the different groups have the same means.

## Content actions

PDF | EPUB (?)

### What is an EPUB file?

EPUB is an electronic book format that can be read on a variety of mobile devices.

#### Collection to:

My Favorites (?)

'My Favorites' is a special kind of lens which you can use to bookmark modules and collections. 'My Favorites' can only be seen by you, and collections saved in 'My Favorites' can remember the last module you were on. You need an account to use 'My Favorites'.

| A lens I own (?)

#### Definition of a lens

##### Lenses

A lens is a custom view of the content in the repository. You can think of it as a fancy kind of list that will let you see content through the eyes of organizations and people you trust.

##### What is in a lens?

Lens makers point to materials (modules and collections), creating a guide that includes their own comments and descriptive tags about the content.

##### Who can create a lens?

Any individual member, a community, or a respected organization.

##### What are tags?

Tags are descriptors added by lens makers to help label content, attaching a vocabulary that is meaningful in the context of the lens.

| External bookmarks

#### Module to:

My Favorites (?)

'My Favorites' is a special kind of lens which you can use to bookmark modules and collections. 'My Favorites' can only be seen by you, and collections saved in 'My Favorites' can remember the last module you were on. You need an account to use 'My Favorites'.

| A lens I own (?)

#### Definition of a lens

##### Lenses

A lens is a custom view of the content in the repository. You can think of it as a fancy kind of list that will let you see content through the eyes of organizations and people you trust.

##### What is in a lens?

Lens makers point to materials (modules and collections), creating a guide that includes their own comments and descriptive tags about the content.

##### Who can create a lens?

Any individual member, a community, or a respected organization.

##### What are tags?

Tags are descriptors added by lens makers to help label content, attaching a vocabulary that is meaningful in the context of the lens.

| External bookmarks