# Sketch a normal curve for the problem above with mean = 0.07 and

Review and Experience Exam Questions for Exam 2

Learning Objectives:

Chapter 17: Thinking encircling fortuity

• Interpret how haphazard plaints bekeep in the incomplete run and in the desire run and how haphazard and

haphazard are not the corresponding fiction.

• Perform basic presumption calculations using die flattens and fabricate tosses.

• Define presumption, and allot the rules for presumption.

• Interpret whether the law of mediums is gentleman.

• Interpret how specific presumption differs from a philosophical or tentative presumption.

Chapter 18: Presumption plummets

• Define a presumption plummet. Form a presumption plummet for a detail legend’s plaints.

• Allot the basic rules of presumption to a legend altitude.

• Correlation probabilities using a presumption plummet, including summing up probabilities or

subtracting probabilities from the entirety.

• Define a sampling dispensation.

Chapter 20: The scion edge: expected esteems

• Define expected esteem, and correlation the expected esteem when ardent a presumption plummet.

• Define the law of extensive gum, and interpret how it is opposed from the mythical “law of

averages.”

• Interpret how casinos and insurance companies alight in duty and frame capital.

Chapter 13: The Normal dispensation

• Confirm facts that is Normally nice.

• Discuss how the shape/position of the Normal incurvation shifts when the plummet disconnection

increases/decreases or when the balance increases/decreases.

• Define the plummetized esteem or Z-score. Correlation the Z-score, and use the Z-score to do

comparisons.

• Correlation probabilities and diminish esteems using the 68%-95%-99.7% (Empirical) Rule.

• Confirm the balance, plummet disconnection, diminish esteem, presumption, and Z-score on a Normal incurvation.

• Use the Normal consideration to get percentiles (probabilities) for presumptuous altitudes and to get Z-scores

in dispose to individualize diminishs for unskilled altitudes using twain > and < in the inequalities.

• Recognize whether a legend is a presumptuous or unskilled Normal dispensation altitude, and perform

the mismisdivert calculations semblanceing set-exact notation, the judicious presumption enumerateenance, and all

essential steps.

2

Chapter 21: What is a belief season?

• Define statistical deduction and interpret when statistical deduction is used.

• Interpret what the belief season balances and whether the results advert to the population or

the specimen.

• Correlation the latitude of fallacy and confirm the latitude of fallacy in a belief declaration.

Explain what loveness of fallacy is familiar in the latitude of fallacy.

• Individualize whether a legend is improve picturesque delay a correlation or a balance.

• Use mismisdivert notation for correlations and balances, twain in the population and the specimen.

• Correlation a belief season for a correlation and for a balance.

• Describe how increasing/decreasing the specimen numerousness or belief flatten shifts the latitude of

fallacy (width of the belief season).

• Allot sparing for using belief seasons.

o Need a isolated haphazard specimen.

o Facts must be calm set-rightly.

o No outliers.

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Practice Exam Questions

These experience exam interrogations are not balancet to be an debilitating schedule. These are barely examples of

questions that keep been asked in the gone-by. You definitely should try started through these examples

delay your fiction fencing, but frame unquestioning that you use the Learning Objectives to form your fiction fencing

and to acceleration you meet other altitudes to experience. Your preceptor uses the Learning Objectives when

writing the exams. The odd-numbered altitudes in your dimensions keep enumerateer-arguments in the tail, and the

StatsPortal website has multifarious numerous resources to acceleration your examineing, especially the Learning Curve

quizzes and the video train. Remember that you are allowed to bear a 1-page (twain margins ok),

handwritten-in-your-own-handwriting, 8 ½” x 11” fiction fencing delay you to the exam. Your indicate should

be on the fiction fencing, and it earn be rate 1 subject-matter on the exam when you round it in.

The exemplification/sampling intention and ethics topics from Exam 1 are relevant throughout the sound

semester and may semblance up on aftercitedcited exams.

1. Before the 2008 presidential antagonism, the Gallup Poll asked a specimen of 1,000 herd for

whom they would opinion for president; 52% said Obama. The latitude of fallacy for a 95%

belief season give-outd by tidings reports of this poll was:

A) ±8% B) ±6% C) ±4% D) ±3% E) ±2%

2. “Margin of fallacy” in this aspect balances that if tnear is no bias

A) integral specimen the Gallup Poll takes earn conclude at mediumest this hinder to the fact.

B) encircling half of the specimens the Gallup Poll takes earn conclude at mediumest this hinder to the fact.

C) encircling 95% of all specimens the Gallup Poll takes earn conclude at mediumest this hinder to the fact.

D) the sampling system is biased—otherwise the poll would constantly surrender the set-exact enumerateer-argument.

E) tnear are important nonsampling fallacys—otherwise the poll would constantly surrender the set-right

3. A Gallup poll reconnoitreed 3,112 opinionrs. An AP poll reconnoitreed 778 opinionrs from the corresponding population

on the upexact corresponding interrogation. How does the latitude of fallacy for a 95% belief season

compare for the Gallup and AP polls?

a. The Gallup latitude of fallacy is bigger than the AP latitude of fallacy.

b. The Gallup latitude of fallacy is the corresponding as the AP latitude of fallacy.

c. The Gallup latitude of fallacy is smaller than the AP latitude of fallacy.

4. The balance is 80 and the plummet disconnection is 10. What is the plummet score for an observation

Suppose that the BAC of novices who absorb five beers varies from novice to novice according to a

Normal dispensation delay balance 0.07 and plummet disconnection 0.01. For interrogations 10 through 13, semblance

5. The medium 99.7% of novices who absorb five beers keep BAC betwixt what two gum?

6. What percent of novices who absorb five beers keep BAC adown 0.09?

7. What BAC do the main 15% of novices keep succeeding absorbing five beers?

8. Sketch a Normal incurvation for the altitude overhead delay balance = 0.07 and plummet disconnection = 0.01.

Label your x-axis from 0.04 to 0.10 in 0.01 increments. Also semblance the how the top 15% of

students (from #7) would be represented on that Normal incurvation.

9. A poker resembleer is dealt meagre operatives for diverse hours. He decides to bet heavily on

the definite operative of the waning on the axioms that succeeding multifarious bad operatives he is due for a

winner.

a) He’s exact, owing the allurings keep to medium out.

b) He’s injustice, owing successive deals are rebellious of each other.

c) He’s exact, owing successive deals are rebellious of each other.

d) He’s injustice, owing his expected allurings are \$0 and he’s adown that now.

10. The presumption of an outconclude of a haphazard lion is

a) either 0 or 1, endureing on whether the lion can really supervene.

b) the correlation of a very desire train of repetitions on which the outconclude supervenes.

c) the balance plus or minus two plummet disconnections.

d) the belief flatten.

5

In legislation facts, a nobility consists of two or past men-folks who speed concertedly and are connected by blood

or espousals. Appropriate an American nobility at haphazard and enumerate the compute of herd it contains. Near is

the assignment of probabilities for your end:

# of men-folks 2 3 4 5 6 7 or past

Probability 0.42 0.23 0.21 0.09 0.03 ???

11. What is the presumption a nobility earn keep 7 or past herd in it? Semblance your is-sue adown.

12. What is the presumption a nobility earn keep past than 2 herd in it? Semblance your is-sue adown.

13. What is the presumption a nobility earn keep 3 or 4 herd in it? Semblance your is-sue adown.

14. What is the expected esteem of the compute of nobility members? Semblance your is-sue adown and

transcribe your enumerateer-argument in the unmitigated.

15. A place of cards contains 52 cards, of which 4 are aces. You are offered the aftercitedcited determine:

describe one card at haphazard from the place. You win \$10 if the card describen is an ace. Otherwise

you waste \$1. If you frame this determine very multifarious occasions, what earn be the balance end?

a) encircling -\$1, owing you earn waste most of the occasion.

b) encircling \$9, owing you earn win \$10 but waste barely \$1.

c) encircling -\$0.15, that is, on the medium you waste encircling 15 cents.

d) encircling \$0.77, that is, on the medium you win encircling 77 cents.

e) encircling \$0 owing the haphazard describe surrenders you a unspotted bet.

16. A place of 52 cards contains 13 nucleuss. Near is another determine: describe one card at

haphazard from the place. If the card describen is a nucleus, you win \$2. Otherwise, you waste \$1.

Compare this determine (wheedle it Determine 2) delay that of the former interrogation (wheedle it Determine 1).

Which one should you promote?

a) Determine 1, owing it has a surpassing expected esteem.

b) Determine 2, owing it has a surpassing expected esteem.

c) Determine 1, owing it has a surpassing presumption of alluring.

d) Determine 2, owing it has a surpassing presumption of alluring.

e) Twain determines are equal indulgent.

6

17. A psychologist imagines that scheduleening to Bach may acceleration herd imagine. She surrenders subjects a set of

puzzles and measures how multifarious they decipher in 5 minutes opportunity scheduleening to Bach. From facts on

multifarious herd, the psychologist individualizes a presumption plummet for solving 1, 2, 3,4 , and 5

puzzles decipherd. The expected esteem she correlations from this presumption plummet is 2.6. The law of

extensive gum says

a) remark whether each of multifarious subjects deciphers a enigma. The correlation who decipher a enigma

earn be hinder to the expected esteem.

b) if you remark five subjects in a row who decipher barely one enigma, the direct diverse subjects are

mitigated to decipher three or foul-mouthed enigmas owing the medium must alight hinder to the expected

value.

c) the expected esteem is set-exact barely in a haphazardized relatively exemplification.

d) remark multifarious subjects and annals how multifarious enigmas each deciphers. The medium earn be hinder

to the expected esteem.

The dispensation of altitudes of adult men is approximately Normal delay balance 69 inches and plummet

disconnection 2.5 inches. Semblance your is-sue. Answers delayout set-exact is-sue earn not accept any belief.

18. What percent of all men are incompleteer than 64 inches?

19. How lofty is a man whose plummetized altitude is z = -0.3? Counter-argument in inches.

20. What percent of all men are loftyer than a man whose altitude is at the 60th percentile?

21. How lofty is a man who is in the 82nd percentile? Counter-argument in inches.

7

The casino frolic craps is inveterate on flattening two dice. Near is the assignment of probabilities to the sum of

the gum on the up faces when two dice are flattened:

Outconclude 2 3 4 5 6 7 8 9 10 11 12

Probability 1/36 2/36 3/36 4/36 5/36 6/36 5/36 4/36 3/36 2/36 1/36

The most niggardly bet in craps is the “ignoring direction.” A ignoring direction bettor wins delayout-delay if either a 7 or an

11 concludes up on the primitive flatten. This is wheedleed a “natural.” Use this advice to enumerateer-argument interrogations 11

through 14.

22. What is the presumption of a plaintual?

a. 2/36 b. 6/36 c. 8/36 d. 12/36 e. 20/36

23. What is the presumption you do not flatten a 7?

a. 6/36 b. 28/36 c. 0 d. 30/36 e. 8/36

24. Gigi has flattened a plaintual on foul-mouthed undeviating tosses of the dice. This excites the gamblers standing

around the consideration. They should recognize that:

a. Gigi has a hot operative, so she is past mitigated to flatten another plaintual.

b. The law of mediums says that Gigi is now hither mitigated to flatten another plaintual.

c. Rolls are rebellious, so the fortuity of flattening another plaintual has not radical.

d. Foul-mouthed undeviating plaintuals are closely impracticable, so the dice are probably loaded.

e. They should not be surprised owing the presumption of foul-mouthed undeviating plaintuals is 2/36.

25. The consideration overhead semblances a fairly-deduced presumption plummet owing:

a. All the probabilities are betwixt 0 and 1.

b. All the probabilities are betwixt -1 and 1.

c. The sum of all the probabilities is uprightly 1.

d. Twain A and C.

e. Twain B and C.

8

26. A frolic involving a couple of dice pays you \$4 delay presumption 16/36, costs you \$2 delay presumption

14/36, and costs you \$6 delay presumption 6/36. What is the expected esteem of the equality of

capital you win or waste succeeding one resemble of the frolic? Semblance your is-sue using 3 decimal places. An

counter-argument delayout set-exact is-sue earn accept no belief.

Fewer US teens fume, absorb than European peers: examine

Fewer teenagers in the United States fume and absorb compared to their European enumerateerparts, but

past use garbages, according to a University of Michigan examine released Friday.

Using facts from 36 European enumerateries plus the United States, researchers plant that 27 percent of US

adolescents had consumed alcohol in the month antecedent to life quizzed by pollsters, compared to 57

percent of Europeans.

Twelve percent of American teens had fumed tobacco, compared to 20 percent for the Europeans,

according to the examine, the fifth of its peel gone 1995 delay a entirety of 100,000 novices olden 15 and 16

taking dissect.

"One of the reasons that smoking and absorbing rates natant adolescents are so considerable inferior near than in

Europe is that twain behaviors keep been depressed and keep reached historically low flattens in the United

States," administer doer Lloyd Johnston said.

"But plain in the prior years of the European reconnoitres, absorbing and smoking by American adolescents

was entirely low by comparison," he said, adding peaceful that "use of unfair garbages is entirely a opposed

matter."

Eighteen percent of the Americans had used marijuana or hashish, a correlation exceeded in Europe barely

in France (24 percent) and Monaco (21 percent).

On medium, barely splain percent of boyish Europeans had used either gist.

Relatively gentle approximation to marijuana and slight awareness of its dangers interpret the figures, according to

the responses that researchers calm from reconnoitre dissecticipants.

The Americans were also the biggest users of all other garbages too marijuana -- such as LSD, ecstasy

and amphetamines -- at 16 percent, compared to six percent across Europe.

"Clearly the United States has attained relatively low rates of use for cigarettes and alcohol, though not

as low as we would love," Johnston said. "But the flatten of unfair garbage use by adolescents is peaceful exceptional

here."

15,400 teenagers in the United States took dissect in the reconnoitre, adesire delay at mediumest 2,400 enumerateerparts in

each of the 36 European nations, the University of Michigan said in a declaration. 9

27. What is the population of attention for this examine?

28. Indicate the most mitigated loveness of fallacy that could collision the meetings in this examine. Interpret your

choice.

29. What was the specimen numerousness for individuals from the US for the popular year?

30. Correlation a 90% belief season (CI) for the correlation of U.S. teenagers that had used

marijuana or hashish (intermittently for the popular year).

31. Suppose you were to shift the belief flatten in interrogation 4 to 95% using the corresponding specimen.

How would the belief season shift? No calculations essential.

a. The belief season would be the corresponding width but shifted to the left.

b. The belief season would be the corresponding width but shifted to the exact.

c. The belief season would keep the corresponding interior but would be stray.

d. The belief season would keep the corresponding interior but would be narrower.

32. What if the specimen numerousness was barely 5000 herd for the 90% belief season in #4. How would

the belief season shift delay this smaller specimen numerousness? No calculations essential.

a. The belief season would be the corresponding width but shifted to the left.

b. The belief season would be the corresponding width but shifted to the exact.

c. The belief season would keep the corresponding interior but would be stray.

d. The belief season would keep the corresponding interior but would be narrower.

33. A fresh poll reputed a belief 95% belief season of 52% ± 3%. The poll

was carried out by telephone, so herd delayout phones are constantly extreme from the

sample. Any fallacys in the decisive results due to barring herd delayout phones:

a. are interposed in the give-outd latitude of fallacy.

b. are in specification to the give-outd latitude of fallacy.

c. can be ignored, owing these herd are not dissect of the population.

d. can be ignored owing this is a nonsampling fallacy.

10

34. The phrase “95% belief” balances

a. our results are gentleman for 9% of the population of all adults.

b. 95% of the population falls delayin the latitude of fallacy we give-out.

c. the presumption is 0.95 that a haphazardly chosen adult falls in the latitude of fallacy we give-out.

d. we got these results using a system that surrenders set-exact enumerateer-arguments in 95% of all specimens.

35. Gallup polled 1,523 adults and 501 teens on whether they generally general of lawful gambling.

63% of adults and 52% of teens said yes. The latitude of fallacy for a 95% belief declaration

encircling teens would be

a. numerouser than for adults, owing the teen specimen is smaller.

b. hither than for adults, owing the teen specimen is smaller.

c. hither than for adults, owing tnear are fewer teens in the population.

d. the corresponding as for adults, owing they twain conclude from the corresponding specimen reconnoitre.

e. Can’t say, owing it endures on what percent of each population was in the specimen.

36. Which of the aftercitedcited systems would retrench the width of a belief

season for a balance, if all else alights the corresponding. You may appropriate past than one enumerateer-argument for

this interrogation.

a. Increase the flatten of belief.

b. Increase the specimen numerousness.

c. Retrench the flatten of belief.

d. Retrench the specimen numerousness.

37. A 95% belief season indicates that:

a. 95% of the likely specimen balances (same-greatness specimens) earn be interposed by the season.

b. 95% of the seasons invented using this way inveterate on corresponding-sized specimens from this

population earn grasp the specimen balance.

c. 95% of the likely population balances earn be interposed by the season.

d. 95% of the seasons invented using this way inveterate on corresponding-sized specimens from this

population earn grasp the population balance.

38. A nationally nice seed-plot tidingspaper conducts a reconnoitre natant novices nationwide integral

year. This year, responses from a isolated haphazard specimen of 204 seed-plot novices to the interrogation

“About how multifarious CDs do you own?” resulted in a specimen balance of 72.8. Inveterate on facts from

former years, the editors of the tidingspaper earn suppose a population plummet disconnection of 7.2.

What is a 95% belief season for the population balance compute of CDs owned by all seed-plot

a. (65.6, 80.0) b. (71.8, 73.8) c. (72.0, 73.6) d. (72.3, 73.3)

11

39. The sound subject-matter of doing a belief season is:

a. To get advice encircling the specimen statistic.

b. To do a census.

c. To like the plummet disconnection.

d. To like the population parameter. 12

1. D

2. C

3. C

4. 1

5. 0.04 and 0.10

6. 97.73%

7. 0.081

8. Semblance a Normal incurvation delay 0.07 in the medium and 0.04 to 0.10 noticeable in plain increments at

proper spacing on either margin. A direction should be describen at 0.081, delay shading to the exact of that

direction and the shading labeled delay “top 15%.”

9. B

10. B

11. 0.02

12. 0.58

13. 0.44

14. 3.14

15. C

16. A

17. D

18. 2.5% (or 2.27% using the consideration)

19. 68.25

20. 40

21. 71.25

22. C

23. D 13

24. C

25. D

26. 0

27. All US and European teens

28. Response fallacy b/c herd jurisdiction lie (other enumerateer-arguments are superficial, but earn endure on the

rationale)

29. 15,400

30. Specimen correlation is 18% delay n = 15,400. The belief season is (0.1749, 0.1851) using Z* =

1.645, but either 1.64 or 1.65 could be used.

31. C

32. C

33. B

34. D

35. A

36. B, C

37. D

38. B

39. D