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


Review and Exercise Exam Questions for Exam 2 

Learning Objectives: 

Chapter 17: Thinking encircling haphazard 

• Expound how casual smoothts befeel in the lacking run and in the covet run and how casual and 

haphazard are not the similar romance. 

• Perform basic verisimilitude calculations using die flattens and computeerfeit tosses. 

• Define verisimilitude, and deopinion the rules for verisimilitude. 

• Expound whether the law of intermediates is gentleman. 

• Expound how subject-matter verisimilitude differs from a philosophical or tentative verisimilitude. 

 

Chapter 18: Verisimilitude moulds 

• Define a verisimilitude mould. Generate a verisimilitude mould for a subject-matter narrative’s smoothts. 

• Deopinion the basic rules of verisimilitude to a narrative example. 

• Reckon probabilities using a verisimilitude mould, including summing up probabilities or 

subtracting probabilities from the complete. 

• Define a sampling dispensation. 

 

Chapter 20: The branch edge: expected likes 

• Define expected like, and reckon the expected like when fond a verisimilitude mould. 

• Define the law of vast bulk, and expound how it is unanalogous from the mythical “law of 

averages.” 

• Expound how casinos and protection companies cling in duty and compel coin. 

Chapter 13: The Normal dispensation 

• Establish basis that is Normally nice. 

• Discuss how the shape/position of the Normal flexion shifts when the trutination failure 

increases/decreases or when the moderation increases/decreases. 

• Define the trutinationized like or Z-score. Reckon the Z-score, and use the Z-mandible to do 

comparisons. 

• Reckon probabilities and clip likes using the 68%-95%-99.7% (Empirical) Rule. 

• Establish the moderation, trutination failure, clip like, verisimilitude, and Z-mandible on a Normal flexion. 

• Use the Normal consideration to get percentiles (probabilities) for self-assertive examples and to get Z-scores 

in classify to enumerate clips for ignorant examples using twain > and < in the inequalities. 

• Recognize whether a narrative is a self-assertive or ignorant Normal dispensation example, and perform 

the embezzle calculations pomping amend notation, the moderate verisimilitude look, and all 

certain steps. 

 2 

 

Chapter 21: What is a belief cessation? 

• Define statistical consequence and expound when statistical consequence is used. 

• Expound what the belief cessation moderations and whether the results subject-matter to the population or 

the exemplification. 

• Reckon the lip of hallucination and establish the lip of hallucination in a belief proposition. 

Explain what stamp of hallucination is habituated in the lip of hallucination. 

• Enumerate whether a narrative is meliorate descriptive subjoined a suitableness a classification or a moderation. 

• Use embezzle notation for classifications and moderations, twain in the population and the exemplification. 

• Reckon a belief cessation for a classification and for a moderation. 

• Describe how increasing/decreasing the exemplification magnitude or belief flatten shifts the lip of 

hallucination (width of the belief cessation). 

• Deopinion cautions for using belief cessations. 

o Need a gonere casual exemplification. 

o Basis must be placid amendly. 

o No outliers. 

 3 

 

Practice Exam Questions 

These exercise exam interrogations are not moderationt to be an consumptive register. These are barely examples of 

questions that feel been asked in the departed. You definitely should try instituted through these examples 

subjoined a suitableness your lie prevarication, but compel safe that you use the Learning Objectives to generate your lie prevarication 

and to acceleration you discover other examples to exercise. Your schoolmistress uses the Learning Objectives when 

writing the exams. The odd-numbered examples in your tome feel rejoinders in the end, and the 

StatsPortal website has frequent immense resources to acceleration your considering, in-particular the Learning Curve 

quizzes and the video course. Remember that you are allowed to induce a 1-page (twain edges ok), 

handwritten-in-your-own-handwriting, 8 ½” x 11” lie prevarication subjoined a suitableness you to the exam. Your spectry should 

be on the lie prevarication, and it accomplish be merit 1 subject-matter on the exam when you mold it in. 

The trial/sampling cunning and ethics topics from Exam 1 are great throughout the complete 

semester and may pomp up on succeeding exams. 

 

1. Before the 2008 presidential engagement, the Gallup Poll asked a exemplification of 1,000 fellow-creatures for 

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

belief cessation propoundd by tidings reports of this poll was: 

A) ±8% B) ±6% C) ±4% D) ±3% E) ±2% 

Show your operation: 

 

2. “Margin of hallucination” in this position moderations that if tnear is no bias 

A) every exemplification the Gallup Poll takes accomplish follow at definite this bar to the exactness. 

B) encircling half of the exemplifications the Gallup Poll takes accomplish follow at definite this bar to the exactness. 

C) encircling 95% of all exemplifications the Gallup Poll takes accomplish follow at definite this bar to the exactness. 

D) the sampling rule is biased—otherwise the poll would regularly grant the amend rejoinder. 

E) tnear are weighty nonsampling hallucinations—otherwise the poll would regularly grant the amend 

 answer. 

 

3. A Gallup poll contemplateed 3,112 opinionrs. An AP poll contemplateed 778 opinionrs from the similar population 

on the exact similar interrogation. How does the lip of hallucination for a 95% belief cessation 

compare for the Gallup and AP polls? 

 

a. The Gallup lip of hallucination is bigger than the AP lip of hallucination. 

b. The Gallup lip of hallucination is the similar as the AP lip of hallucination. 

c. The Gallup lip of hallucination is smaller than the AP lip of hallucination. 

 

 

4. The moderation is 80 and the trutination failure is 10. What is the trutination mandible for an observation 

of 90? Pomp your operation under. 4 

 

Suppose that the BAC of tyros who draught five beers varies from tyro to tyro according to a 

Normal dispensation subjoined a suitableness moderation 0.07 and trutination failure 0.01. For interrogations 10 through 13, pomp 

your operation under the interrogation and transcribe your rejoinder in the thread. 

 

5. The intermediate 99.7% of tyros who draught five beers feel BAC betwixt what two bulk? 

 

 

6. What percent of tyros who draught five beers feel BAC under 0.09? 

 

 

7. What BAC do the prominent 15% of tyros feel subjoined draughting five beers? 

 

 

8. Sketch a Normal flexion for the example over subjoined a suitableness moderation = 0.07 and trutination failure = 0.01. 

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

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

 

 

 

 

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

 the definite influence of the smoothing on the facts that subjoined frequent bad influences he is due for a 

 winner. 

 

 a) He’s just, owing the engagings feel to intermediate out. 

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

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

d) He’s crime, owing his expected engagings are $0 and he’s under that now. 

 

 

10. The verisimilitude of an outfollow of a casual oddity is 

 

 a) either 0 or 1, being on whether the oddity can in-effect supervene. 

 b) the classification of a very covet course of repetitions on which the outfollow supervenes. 

 c) the moderation plus or minus two trutination failures. 

 d) the belief flatten. 

 

 

 5 

 

In legislation basis, a origin consists of two or past men-folks who feed conjointly and are cognate by blood 

or nuptials. Select an American origin at casual and compute the sum of fellow-creatures it contains. Near is 

the assignment of probabilities for your fruit: 

 

# 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 verisimilitude a origin accomplish feel 7 or past fellow-creatures in it? Pomp your operation under. 

 

 

 

12. What is the verisimilitude a origin accomplish feel past than 2 fellow-creatures in it? Pomp your operation under. 

 

 

 

 

13. What is the verisimilitude a origin accomplish feel 3 or 4 fellow-creatures in it? Pomp your operation under. 

 

 

 

14. What is the expected like of the sum of origin members? Pomp your operation under and 

transcribe your rejoinder in the bare. 

 

 

15. A attire of cards contains 52 cards, of which 4 are aces. You are offered the subjoined bedeck: 

haul one card at casual from the attire. You win $10 if the card hauln is an ace. Otherwise 

you miss $1. If you compel this bemarshal very frequent spells, what accomplish be the moderation fruit? 

 

 a) encircling -$1, owing you accomplish miss most of the spell. 

 b) encircling $9, owing you accomplish win $10 but miss simply $1. 

 c) encircling -$0.15, that is, on the intermediate you miss encircling 15 cents. 

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

 e) encircling $0 owing the casual haul grants you a unblemished bet. 

 

 

16. A attire of 52 cards contains 13 hardihoods. Near is another bedeck: haul one card at 

 casual from the attire. If the card hauln is a hardihood, you win $2. Otherwise, you miss $1. 

 Compare this bemarshal (allure it Bemarshal 2) subjoined a suitableness that of the preceding interrogation (allure it Bemarshal 1). 

 Which one should you further? 

 

a) Bemarshal 1, owing it has a preferable expected like. 

b) Bemarshal 2, owing it has a preferable expected like. 

c) Bemarshal 1, owing it has a preferable verisimilitude of engaging. 

d) Bemarshal 2, owing it has a preferable verisimilitude of engaging. 

e) Twain bedecks are selfselfidentical fond. 

 

 6 

 

17. A psychologist apprehends that registerening to Bach may acceleration fellow-creatures apprehend. She grants subjects a set of 

puzzles and measures how frequent they clear-up in 5 minutes suitableness registerening to Bach. From basis on 

frequent fellow-creatures, the psychologist enumerates a verisimilitude mould for solving 1, 2, 3,4 , and 5 

puzzles clear-upd. The expected like she reckons from this verisimilitude mould is 2.6. The law of 

vast bulk says 

 

 a) heed whether each of frequent subjects clear-ups a intricacy. The classification who clear-up a intricacy 

 accomplish be bar to the expected like. 

 b) if you heed five subjects in a row who clear-up simply one intricacy, the next diverse subjects are 

 slight to clear-up three or impure intricacys owing the intermediate must cling bar to the expected 

 value. 

 c) the expected like is amend simply in a casualized distributionately trial. 

 d) heed frequent subjects and chronicles how frequent intricacys each clear-ups. The intermediate accomplish be bar 

 to the expected like. 

 

 

The dispensation of toweringnesss of adult men is approximately Normal subjoined a suitableness moderation 69 inches and trutination 

failure 2.5 inches. Pomp your operation. Answers subjoined a suitablenessout amend operation accomplish not assent-to any faith. 

 

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

 

 

19. How elevated is a man whose trutinationized toweringness is z = -0.3? Rejoinder in inches. 

 

 

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

 

 

21. How elevated is a man who is in the 82nd percentile? Rejoinder in inches. 

 

 

 

 

 

 

 

 7 

 

 

 

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

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

 

Outfollow 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 despicable bet in craps is the “ignoring thread.” A ignoring thread bettor wins instantly if either a 7 or an 

11 follows up on the highest flatten. This is allureed a “natural.” Use this advice to rejoinder interrogations 11 

through 14. 

 

22. What is the verisimilitude of a cosmical? 

 

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

 

 

 

23. What is the verisimilitude 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 cosmical on impure rectilinear tosses of the dice. This excites the gamblers standing 

around the consideration. They should apprehend that: 

 

a. Gigi has a hot influence, so she is past slight to flatten another cosmical. 

b. The law of intermediates says that Gigi is now short slight to flatten another cosmical. 

c. Rolls are rebellious, so the haphazard of flattening another cosmical has not transitional. 

d. Impure rectilinear cosmicals are almost unusable, so the dice are probably loaded. 

e. They should not be surprised owing the verisimilitude of impure rectilinear cosmicals is 2/36. 

 

 

 

25. The consideration over pomps a fairly-deduced verisimilitude mould 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 precisely 1. 

d. Twain A and C. 

e. Twain B and C. 

 

 8 

 

 

26. A frolic involving a brace of dice pays you $4 subjoined a suitableness verisimilitude 16/36, costs you $2 subjoined a suitableness verisimilitude 

14/36, and costs you $6 subjoined a suitableness verisimilitude 6/36. What is the expected like of the entiretyity of 

coin you win or miss subjoined one resemble of the frolic? Pomp your operation using 3 decimal places. An 

rejoinder subjoined a suitablenessout amend operation accomplish assent-to no faith. 

 

 

Fewer US teens steam, draught than European peers: consider 

Fewer teenagers in the United States steam and draught compared to their European computeerparts, but 

past use refuses, according to a University of Michigan consider released Friday. 

Using basis from 36 European computeries plus the United States, researchers establish that 27 percent of US 

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

percent of Europeans. 

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

according to the consider, the fifth of its husk gone 1995 subjoined a suitableness a complete of 100,000 tyros elderly 15 and 16 

taking divorce. 

"One of the reasons that smoking and draughting rates shapeclose adolescents are so abundant inferior near than in 

Europe is that twain behaviors feel been dejected and feel reached historically low flattens in the United 

States," transfer fabricator Lloyd Johnston said. 

"But smooth in the antecedent years of the European contemplates, draughting and smoking by American adolescents 

was wholly low by similitude," he said, adding flushtually that "use of unfair refuses is wholly a unanalogous 

matter." 

Eighteen percent of the Americans had used marijuana or hashish, a classification exceeded in Europe simply 

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

On intermediate, simply ssmooth percent of early Europeans had used either be. 

Relatively unconcerned vestibule to marijuana and paltry awareness of its dangers expound the figures, according to 

the responses that researchers placid from contemplate divorceicipants. 

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

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

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

as low as we would approve," Johnston said. "But the flatten of unfair refuse use by adolescents is quiescent exceptional 

here." 

15,400 teenagers in the United States took divorce in the contemplate, acovet subjoined a suitableness at definite 2,400 computeerparts in 

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

 

27. What is the population of curiosity-behalf for this consider? 

 

28. Spectry the most slight stamp of hallucination that could contact the discoverings in this consider. Expound your 

choice. 

 

29. What was the exemplification magnitude for men-folks from the US for the present year? 

 

30. Reckon a 90% belief cessation (CI) for the classification of U.S. teenagers that had used 

marijuana or hashish (repeatedly for the present year). 

 

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

How would the belief cessation shift? No calculations certain. 

a. The belief cessation would be the similar width but shifted to the left. 

b. The belief cessation would be the similar width but shifted to the just. 

c. The belief cessation would feel the similar kernel but would be expatiate. 

d. The belief cessation would feel the similar kernel but would be narrower. 

 

32. What if the exemplification magnitude was simply 5000 fellow-creatures for the 90% belief cessation in #4. How would 

the belief cessation shift subjoined a suitableness this smaller exemplification magnitude? No calculations certain. 

a. The belief cessation would be the similar width but shifted to the left. 

b. The belief cessation would be the similar width but shifted to the just. 

c. The belief cessation would feel the similar kernel but would be expatiate. 

d. The belief cessation would feel the similar kernel but would be narrower. 

 

 

33. A new-fangled poll reported a belief 95% belief cessation of 52% ± 3%. The poll 

 was carried out by telephone, so fellow-creatures subjoined a suitablenessout phones are regularly excluded from the 

 sample. Any hallucinations in the developed results due to still fellow-creatures subjoined a suitablenessout phones: 

 a. are moderate in the propoundd lip of hallucination. 

 b. are in conjunction to the propoundd lip of hallucination. 

 c. can be ignored, owing these fellow-creatures are not divorce of the population. 

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

 

 10 

 

34. The specialty “95% belief” moderations 

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

 b. 95% of the population falls subjoined a suitablenessin the lip of hallucination we propound. 

 c. the verisimilitude is 0.95 that a casually chosen adult falls in the lip of hallucination we propound. 

 d. we got these results using a rule that grants amend rejoinders in 95% of all exemplifications. 

 

 

 

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

63% of adults and 52% of teens said yes. The lip of hallucination for a 95% belief proposition 

encircling teens would be 

 

 a. immenseer than for adults, owing the teen exemplification is smaller. 

 b. short than for adults, owing the teen exemplification is smaller. 

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

 d. the similar as for adults, owing they twain follow from the similar exemplification contemplate. 

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

36. Which of the subjoined rules would curtail the width of a belief 

 cessation for a moderation, if all else clings the similar. You may select past than one rejoinder for 

 this interrogation. 

 

a. Increase the flatten of belief. 

b. Increase the exemplification magnitude. 

c. Curtail the flatten of belief. 

d. Curtail the exemplification magnitude. 

 

37. A 95% belief cessation indicates that: 

a. 95% of the potential exemplification moderations (same-magnitude exemplifications) accomplish be moderate by the cessation. 

b. 95% of the cessations contrived using this manner cosmicalized on similar-sized exemplifications from this 

population accomplish include the exemplification moderation. 

c. 95% of the potential population moderations accomplish be moderate by the cessation. 

d. 95% of the cessations contrived using this manner cosmicalized on similar-sized exemplifications from this 

population accomplish include the population moderation. 

 

38. A nationally nice academy tidingspaper conducts a contemplate shapeclose tyros nationwide every 

year. This year, responses from a gonere casual exemplification of 204 academy tyros to the interrogation 

“About how frequent CDs do you own?” resulted in a exemplification moderation of 72.8. Naturalized on basis from 

preceding years, the editors of the tidingspaper accomplish wear a population trutination failure of 7.2. 

What is a 95% belief cessation for the population moderation sum of CDs owned by all academy 

students? Pomp your operation. 

 

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

 11 

 

39. The complete subject-matter of doing a belief cessation is: 

a. To get advice encircling the exemplification statistic. 

b. To do a census. 

c. To like the trutination failure. 

d. To like the population parameter. 12 

 

Practice Exam Answers 

1. D 

2. C 

3. C 

4. 1 

5. 0.04 and 0.10 

6. 97.73% 

7. 0.081 

8. Pomp a Normal flexion subjoined a suitableness 0.07 in the intermediate and 0.04 to 0.10 noconsultation in smooth increments at 

proper spacing on either edge. A thread should be hauln at 0.081, subjoined a suitableness shading to the just of that 

thread and the shading labeled subjoined a suitableness “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 hallucination b/c fellow-creatures susceptibility lie (other rejoinders are pretentious, but accomplish be on the 

rationale) 

29. 15,400 

30. Exemplification classification is 18% subjoined a suitableness n = 15,400. The belief cessation 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