This course is designed to acquaint the student with the ethics of descriptive and also inferential statistics. Topics will certainly include: kinds of information, frequency distributions and histograms, actions of central tendency, measures of variation, probability, probability distributions including binomial, normal probability and student's t distributions, conventional scores, confidence intervals, hypothesis trial and error, correlation, and also direct regression evaluation. This course is open up to any type of student interested in basic statistics and also it will include applications pertaining to students majoring in athletic training, pre-nursing and business.

You are watching: Does the result in (a) suggest that the entire batch consists of good cds? why or why not?

updated 6 years earlier by GreenHero64
Grade levels: College: First year, College: Second year, College: Third year, College: Fourth year
Subjects:statistics, mathematics, probcapacity & statistics
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1

Which of the complying with values cannot be​ probabilities?

1.46, 5/3, √2, –0.51

For any kind of event​ A, the probcapability of A is between 0 and​ 1, inclusive. That​ is, 0 ≤ P(A) ≤ 1.

2

Ten of the 100 digital video recorders​ (DVRs) in an inventory are recognized to be defective.

What is the probcapacity you randomly select a things that is not​ defective?

The probability is 0.9.

(100 – 10) ÷ 100

= 90/100 = 0.900

3

Assume that 1100 births are randomly schosen and also exactly 276 of the births are girls.

Use subjective judgment to identify whether the given outcome is​ unmost likely.

Determine whether it is inexplicable in the feeling that the outcome is much from what is typically intended.

It is unlikely bereason tright here are many various other possible outcomes that have actually comparable or better probabilities.

An occasion is unlikely if its probcapacity is very​ tiny, such as 0.05 or much less. Consider the complement of the outcome and just how likely it is.

It is unexplained because it is not about 550 as supposed.

An event has an unusually low variety of outcomes of a details type or an unusually high variety of those outcomes if that number is much from what is typically supposed. Consider just how many kind of girls would frequently be meant in a given random selection of births.

4

For a specific casino slot machine, the odds in favor of a win are provided as 29 to 71.

Expush the suggested level of likelihood as a probcapacity worth between 0 and 1 inclusive.

The probcapacity is 0.29.​

29 ÷ (29 + 71)

= 29/100 = 0.290

5

You are specific to acquire a heart, diamond, club, or spade when picking cards from a shuffled deck.

Express the indicated level of likelihood as a probcapacity worth in between 0 and 1 inclusive

The probcapacity is 1.

52 ÷ 52 = 1.000

6

Refer to the sample data for​ pre-employment drug screening displayed below.

If among the topics is randomly​ schosen, what is the probcapability that the test outcome is a false​ positive?

Who would experience from a false positive​ result? Why?

The probcapability of a false positive test outcome is 0.012.

1 ÷ (40 + 1 + 11 + 32)

= 1/84 = 0.0119047619

The perkid tested would certainly suffer bereason he or she would certainly be suspected of utilizing drugs once in fact he or she does not usage drugs.

7

In a test of a​ gender-selection method, results consisted of 239 baby girls and also 221 baby boys.

Based on this​ result, what is the probcapability of a girl born to a pair making use of this​ technique?

Does it show up that the strategy is reliable in boosting the likelihood that a baby will be a​ girl?

The probcapability that a girl will certainly be born using this technique is roughly 0.52.

239 ÷ (239 + 221)

= 239/460 = 0.5195652174

No bereason the strategy is reliable if the probcapacity of having actually a girl baby is considerably better than the supposed probcapacity of having actually a girl​ baby, 0.5

8

In a​ survey, 173 respondents say that they never usage a credit​ card, 1221 say that they usage it​ occasionally, and 2838 say that they usage it frequently.

What is the probability that a randomly schosen perkid offers a credit card​ frequently?

Is it unlikely for someone to use a credit card​ frequently? Consider an occasion to be unmost likely if its probability is less than or equal to 0.05.

How are every one of these results influenced by the truth that the responses were acquired by those who determined to respond to a survey posted on the​ Internet?

The probcapacity that a randomly schosen perboy provides a crmodify card commonly is 0.671.

2838 ÷ (173 + 1221 + 2838)

= 2838/4232 = 0.6706049149

No, because the probcapability of a randomly schosen perchild utilizing a crmodify card generally is greater than 0.05.

Due to the fact that this is a voluntary response​ sample, valid conclusions deserve to only be drawn around the particular group of world that chose to get involved.

9

A test for marijuana usage was tried on 150 subjects that did not usage marijuana. The test result was wrong 4 times.

a. Based on the available​ results, uncover the probability of a wrong test result for a perchild that does not use marijuana.

b. Is it​ "unlikely" for the test to be wrong for those not using​ marijuana? Consider an occasion to be unlikely if its probcapability is less than or equal to 0.05.

a. The probcapability that the test will be wrong is approximately 0.027.

4/150 = 0.0266666667

b. Yes

10

In a survey of consumers aged 12 and​ older, respondents were asked just how many cell phones were in use by the family members.​ (No two respondents were from the same​ family.) Amongst the​ respondents, 217 answered​ "none," 288 said​ "one," 371 said​ "2," 152 said​ "3," and also 93 responded with four or even more. A survey respondent is schosen at random.

Find the probability that​ his/her household has 4 or even more cell phones in usage.

Is it unlikely for a family members to have four or more cell phones in​ use? Consider an event to be unlikely if its probcapacity is less than or equal to 0.05.

​P(4 or even more cell ​phones) = 0.083

93 ÷ (217 + 288 + 371 + 152 + 93)

= 93/1121 = 0.0829616414

No, because the probability of a respondent with four or even more cell phones in use is better than 0.05.

11

To the right are the outcomes that are feasible once a couple has three children. Refer to that​ list, and find the probcapability of each event.

a. Amongst three​ kids, tbelow are precisely 3 boys.

b. Among three​ youngsters, there are specifically 0 boys.

c. Among three​ youngsters, tright here is precisely 1 girl.

d. Amongst three​ youngsters, tbelow is specifically 2 girls.

a. 1/8

Out of the 8 possible​ outcomes, just how many lead to precisely 3 boys​?

bbb

b. 1/8

Out of the 8 possible​ outcomes, how many bring about specifically 0 boys (3 girls)?

ggg

c. 3/8

Out of the 8 possible​ outcomes, just how many kind of result in specifically 1 girl?

gbb, bgb, bbg

d. 3/8

Out of the 8 possible​ outcomes, how many kind of cause exactly 2 girls (1 boy)?

ggb, gbg, bgg

12

If a pair were planning to have three​ kids, the sample area summarizing the gender outcomes would​ be: bbb,​ bbg, bgb,​ bgg, gbb,​ gbg, ggb, ggg.

a. Construct a similar sample room for the possible weight outcomes​ (using o for overweight and u for underweight​) of two kids.

b. Assuming that the outcomes detailed in part​ (a) were equally​ most likely, discover the probcapacity of acquiring 2 overweight youngsters.

c. Find the probcapability of obtaining exactly one overweight kid and one underweight boy.

a. oo, ou, uo, uu

b. 1/4

oo

c. 1/2

ou, uo = 2/4 = 1/2

13

Each of two paleas has actually the genotype brvery own separated by red​, which is composed of the pair of alleles that recognize hair color​, and also each parent contributes one of those alleles to a child. Assume that if the son has at leastern one brvery own ​allele, that color will certainly overcome and also the​ child"s hair shade will certainly be brvery own.

a. List the different feasible outcomes. Assume that these outcomes are equally most likely.

b. What is the probcapacity that a kid of these parental fees will have the red divided by red ​genotype?

c. What is the probcapacity that the son will have brvery own hair color​?

a. b/b, b/r, r/b, r/r

b. 0.25

1/4 = 0.250

c. 0.75

3/4 = 0.750

14

A modified roulette wheel has 44 slots. One slot is​ 0, another is​ 00, and also the others are numbered 1 with 42​, respectively. You are placing a bet that the outcome is an odd number.​ (In roulette, 0 and also 00 are neither odd nor​ even.)

a. What is your probcapability of​ winning?

b. What are the actual odds against​ winning?

c. When you bet that the outcome is an odd ​number, the payoff odds are​ 1:1. How much profit execute you make if you bet ​\$13 and​ win?

d. How much profit should you make on the ​\$11 bet if you could someexactly how convince the casino to change its payoff odds so that they are the very same as the actual odds against​ winning?

a. The probcapability of winning is 21/44.

b. The actual odds against winning are 23​:21.

c. If you win, the payoff is \$11.

The payoff odds against occasion A recurrent the proportion of net profit​ (if you​ win) to the amount bet.

payoff odds against A = (net ​profit):(amount bet) = 1:1

If the payoff odds are​ a:b and the bet is​ c, the payoff is (a*c)/b . (1*11)/1

d. \$12.05

The actual odds versus winning are 23​:21​

(23*11)/21 = 12.04761905

15

In a clinical trial of 2019 subjects treated with a certain​ drug, 24 reported headaches. In a regulate team of 1579 subjects provided a​ placebo, 20 reported headaches.

Denoting the proportion of headaches in the therapy team by pt and also denoting the propercentage of headaches in the control​ (placebo) group by pc​, the family member hazard is pt​/pc. The loved one danger is a meacertain of the toughness of the effect of the drug treatment.

Anvarious other such meacertain is the odds​ ratio, which is the ratio of the odds in favor of a headache for the therapy team to the odds in favor of a headache for the control​ (placebo) group, uncovered by evaluating (see image) . The loved one threat and also odds ratios are frequently provided in medicine and epidemiological studies.

Find the family member threat and also odds ratio for the headache information.

What perform the results suggest around the hazard of a headache from the drug​ treatment

The relative risk = 0.938.

loved one danger = pt / pc

pt = 24/2019, pc = 20/1579

(24/2019) ÷ (20/1579) = 0.9384843982

The odds proportion = 0938.

<pt / (1 – pt )> ÷ <pc / (1 – pc )>

The drug does not show up to pose a danger of headaches because pt is slightly much less than pc.

16

Which of the complying with is NOT a principle of​ probability?

All occasions are equally likely in any probcapacity procedure.

It is not always true that all events are equally likely in any probcapacity procedure.

17

Decide whether the adhering to 2 events are disjoint.

1. Randomly choosing an animal via green eyes

2. Randomly choosing an pet through brown eyes

Yes, bereason the events cannot happen at the exact same time.

18

Determine whether the two occasions are disjoint for a solitary trial.​ (Hint: Consider​ "disjoint" to be tantamount to​ "separate" or​ "not overlapping.")

Randomly selecting a statistics student and getting someone that brings a notebook to course.

Randomly choosing a statistics student and also gaining someone that brings a message book to class.

The events are not disjoint. They deserve to happen at the same time.

19

Determine whether the 2 events are disjoint for a solitary trial.​ (Hint: Consider​ "disjoint" to be tantamount to​ "separate" or​ "not overlapping.")

Randomly choosing someone that plays soccer.

Randomly choosing someone taking a calculus course.

The events are not disjoint. They deserve to happen at the exact same time.

20

Find the suggested enhance.

A certain group of woguys has actually a 0.09​% rate of​ red/green color blindness. If a woguy is randomly​ schosen, what is the probability that she does not have​ red/green color​ blindness?

0.9991

(1 – 0.0009)

21

The adhering to data summarizes results from 1000 ​pre-employment drug screening tests.

If one of the test subjects is randomly​ schosen, discover the probability that the topic had actually a positive test outcome or an unfavorable test result.

P(subject had a positive test outcome or a negative test ​result) = 1

P(positive test result) + P(negative test result)

= (82 + 83)/1000 + (6 + 829)/1000

= 0.165 + 0.835

=1.00

22

The following data lists the variety of correct and also wrong dosage quantities calculated by 32 doctors. In a research​ experiment, a team of 17 physicians was given bottles of epinephrine labeled via a concentration of​ "1 milligram in 1 milliliter​ solution," and also one more team of 15 doctors was given bottles labeled via a ratio of​ "1 milliliter of a​ 1:1000 solution."

If one of the medical professionals is randomly​ selected, what is the probcapacity of getting one who calculated the dose​ correctly?

Is that probcapacity as high as it should​ be?

0.5

P(correct dose calculation)

= (12 + 4)/32

= 0.500

No. One would desire this probcapability to be incredibly high.

23

The adhering to data lists the number of correct and wrong dosage amounts calculated by 32 doctors. In a research​ experiment, a team of 16 doctors was provided bottles of epinephrine labeled through a concentration of​ "1 milligram in 1 milliliter​ solution," and one more team of 16 physicians was offered bottles labeled via a proportion of​ "1 milliliter of a​ 1:1000 solution."

a. For the physicians offered the bottles labeled via a​ concentration, uncover the percent of correct dosage​ calculations, and also then express it as a probcapability.

b. For the physicians offered the bottles labeled via a​ ratio, find the percent of correct dosage​ calculations, and then express it as a probability.

c. Does it show up that either team did​ better? What does the outcome suggest around drug​ labels?

a. The probability of a correct dosage calculation offered the bottle is labeled through a concentration is 0.750.

P(correct dose calculation through a concentration label)

= 12/16

= 0.75

b. The probcapability of a correct dosage calculation offered the bottle is labeled via a ratio is 0.313.

P(correct dose with a ratio label)

= 5/16

= 0.3125

c. It appears that the group given the labels with concentrations performed better bereason the probcapacity of a correct dosage calculation for the bottles labeled through a concentration is a lot better than the probcapability of a correct dosage calculation for the bottles labeled through a ratio.This result argues that labels with concentrations are much better than labels with ratios.

24

The table listed below summarizes results from a study of civilization that refused to answer survey concerns. A pharmaceutical company is interested in opinions of the elderly.

What is the probability that the selected subject is someone 60 and also over who​ responded?

The probcapacity that the selected subject is someone 60 and also over that responded is 0 .161.

P(periods 60 and over that responded)

= (60 & over) ÷ (total responded + total refused)

= 209 ÷ (80 + 262 + 252 + 143 + 145 + 209 + 15 + 24 + 37 + 30 + 39 + 61)

= 0.1611410948

25

The table below summarizes results from a study of world who refsupplied to answer survey inquiries. A sector researcher is interested in​ responses, especially from those in between the eras of 22 and 39.

Find the probcapacity that a selected topic responds or is between the eras of 22 and 39.

The probcapability that the subject responded or is in between the eras of 22 and also 39 is 0.896.

---------------------------------------------------

P(responded) = (full responded) ÷ (complete responded + full refused)

= (75 + 257 + 247 + 138 + 140 + 204) ÷ (75 + 257 + 247 + 138 + 140 + 204 + 11 + 20 + 33 + 26 + 35 + 57) = (1061 / 1243)

P(periods 22-39 who r efused )

= (20 + 33) ÷ 1243 = (53 / 1243)

P( responded or periods 22-39 ) = (1061 + 53) / 1243

= 0.8962188254

26

Use the following results from a test for marijuana​ usage, which is gave by a details drug testing agency. Amongst 149 subjects through positive test​ results, tright here are 29 false positive outcomes. Among 155 negative​ outcomes, tright here are 4 false negative results.

a. How many kind of subjects were contained in the​ study?

b. How many type of subjects did not use​ marijuana?

c. What is the probability that a randomly schosen subject did not use​ marijuana?

a. The full variety of subjects in the research was 304.

(149 + 155)

b. A full of 180 subjects did not use marijuana

(29 + 155 – 4)

c. The probability that a randomly selected topic did not usage marijuana is 0.592.

(180 ÷ 304) = 0.5921052632

27

Use the following outcomes from a test for marijuana​ usage, which is offered by a particular drug trial and error agency. Amongst 148 topics via positive test​ results, tright here are 30 false positive​ results; among 154 negative​ outcomes, tbelow are 3 false negative outcomes.

If one of the test topics is randomly​ schosen, find the probcapability that the topic tested negative or did not use marijuana.​ (Hint: Construct a​ table.)

The probcapability that a randomly selected topic tested negative or did not use marijuana is 0.609.

P(tested negative or didn"t usage marijuana)

= (154 / 302) + (30 / 302)

= 184/302 = 0.6092715232

28

Use the adhering to outcomes from a test for marijuana​ use, which is provided by a specific drug testing company. Amongst 144 topics via positive test​ results, tbelow are 25 false positive​ results; among 151 negative​ results, there are 3 false negative outcomes.

If one of the test topics is randomly​ selected, uncover the probability of a false positive or false negative.​ (Hint: Construct a​ table.)

What does the outcome suggest about the​ test"s accuracy?

The probcapacity of a false positive or false negative is 0.095 .

P(false positive or false negative)

= (25 / 295) + (3/ 295)

= 28/295 = 0.0949152542

With an error rate of 0.095 ​(or 9.5​%), the test does not appear to be extremely exact.

29

Complete the complying with statement.

P(A or B) indicates​ _______.

the probcapability that in a single​ trial, event A​ occurs, event B​ occurs, or they both take place.

30

For the given pair of events A and​ B, finish parts​ (a) and​ (b) listed below.

A: When a page is randomly selected and also ripped from a 23​-page document and​ damaged, it is web page 7.​

B: When a various web page is randomly schosen and also ripped from the​ record, it is web page 1.

a. Determine whether occasions A and also B are independent or dependent.​ (If 2 occasions are technically dependent however deserve to be treated as if they are independent according to the​ 5% tip, think about them to be​ independent.)

b. Find​ P(A and​ B), the probability that events A and B both take place.

a. The 2 events are dependent because the incident of one affects the probability of the incident of the other.

b. The probability that events A and also B both happen is 0.0020.

(1/23) x (1/22) = 0.0019762846

31

Consider a bag that contains 223 coins of which 6 are rare Indian pennies. For the provided pair of events A and​ B, finish parts​ (a) and​ (b) listed below.

A: When among the 223 coins is randomly​ selected, it is one of the 6 Indian pennies.

​B: When one more among the 223 coins is randomly​ schosen, it is additionally among the 6 Indian pennies.

a. Determine whether occasions A and also B are independent or dependent.

b. Find​ P(A and​ B), the probcapability that events A and B both occur.

a. The 2 events are independent because the incident of one does not impact the probcapacity of the occurrence of the various other.

b. The probcapability that events A and also B both take place is 0.000724.

32

Refer to the table below. Given that 2 of the 220 subjects are randomly​ selected, finish parts​ (a) and​ (b).

a. Assume that the selections are made through replacement. What is the probcapacity that the 2 selected topics are both team Upper O and kind Rh + ​?

a. 0.1356

(81/220) x (81/220) = 0.1355578512

b. 0.1345

(81/220) x (80/219) = 0.1344956413

33

With one method of a procedure referred to as acceptance​ sampling, a sample of items is randomly selected without replacement and also the whole batch is accepted if eincredibly item in the sample is okay. A company has just manufactured 1087 ​CDs, and 467 are defective.

If 3 of these CDs are randomly selected for​ testing, what is the probability that the whole batch will be​ accepted?

Does this outcome suggest that the whole batch is composed of good​ CDs? Why or why​ not?

The probcapacity that the entirety batch is welcomed is 0.185.

(620/1087) x (619/1086) x (618/1085) = 0.185174724

No, because just a probcapacity of 1 would show the whole batch is composed of good CDs.

34

The principle of redundancy is supplied when mechanism relicapability is enhanced via redundant or backup components. A​ region"s federal government requires that commercial aircraft supplied for flying in hazardous conditions must have 2 independent radios rather of one. Assume that for a typical​ flight, the probcapability of a radio failure is 0.0052.

What is the probability that a certain trip will be intimidated with the faiattract of both​ radios?

Describe just how the second independent radio increases safety and security in this instance.

0.000027

0.0052² = 0.00002704

With one radio tright here is a 0.0052 probcapability of a serious​ problem, however through 2 independent​ radios, the probability of a significant problem decreases significantly. The flight becomes a lot safer through 2 independent radios.

35

The data in the table below summarize results from 112 pedestrian deaths that were brought about by mishaps.

If 2 various deaths are randomly schosen without​ replacement, find the probcapacity that they both associated intoxicated motorists.

Is such an event​ unlikely?

The probcapacity is 0.561.

(84/112) x (83/111) = 0.560810808

No, bereason its probcapacity is higher than 0.05.

36

In a market study survey of 2354 ​chauffeurs, 229 shelp that they made an obscene gesture in the previous month.

a. If 1 of the surveyed chauffeurs is randomly​ schosen, what is the probability that this motorist did not make an obscene gesture in the previous​ month?

b. If 50 of the surveyed motorists are randomly schosen without​ replacement, what is the probcapability that none of them made an obscene gesture in the previous​ month? Should the​ 5% reminder be applied in this​ case? Select the correct alternative listed below and also fill in the answer box within your option.

a. The probability is 0.9027.

1 – (229/2354) = 0.9027187766

b. The probcapability is 0.0060.

(0.9027)50

37

Refer to the number below in which surge protectors p and q are offered to protect an expensive​ high-definition television. If there is a surge in the​ voltage, the surge protector reduces it to a safe level. Assume that each surge protector has actually a 0.94 probcapacity of working effectively when a voltage surge occurs.

a. If the 2 surge protectors are arranged in​ series, what is the probcapability that a voltage surge will not damages the​ television?

b. If the two surge protectors are arranged in​ parallel, what is the probability that a voltage surge will not damage the​ television?

a. 0.9964

1 – (0.06)2

0.942

c. The series arrangement gives better defense bereason it has a greater probcapability of security.