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Question 62833: Dave puts a collection of 15 books on a bookshelf in a random order. Among the books are 2 fiction and 13 nonfiction books. Whart is the probability that the 2 fiction books will be all together on the left side of the shelf and the 13 nonfiction all together on the right side of the shelf?
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Question 62840: Numbers is a game where you bet $1.00 on any three-digit number from 000 to 999. If your number comes up, you get $600.00. Find the expected net winnings.
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Question 62838: If 5 apples in a barrel of 25 apples are rotten, what is the expected number of rotten apples in a random sample of 2 apples?
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Question 62837: If 3 balls are drawn at random from a bag containing 3 red and 4 blue balls, what is the expected number of red balls in the sample?
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Question 62835: Four cards are numbered 1 through 4. Two of these cards are chosen at random without replacement and the numbers on them are multiplied. Find the expected value of this product.
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Question 62828: In a lottery, the player selects six numbers from the numbers 1-30. There are six winning numbers (all different) which are selected at random from the numbers 1-30. To win a prize, the ticket must contain three or more of the winning numbers. If you buy one lottery ticket, determine the probability that your ticket contains exactly three winning numbers.
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Question 62830: In A batch of 8000 clock radios 9% are defective. A sample of 6 clock radios is randomly selected without replacement from the 8,000 and tested. The entire batch will be rejected if at least one of those tested is defective. What is the probability that the entire batch will be rejected?
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Question 62831: In a blood testing procedure, blood samples from 6 people are combined into one mixture. The mixture will only test negative if all the individual samples are negative. If the probability that an individual sample tests positive is 0.12, what is the probability that the mixture will test positive?
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Question 62853: If 3 digits are chosen and each digit is equally likely to be chosen, what is the probability that all digits are the same?
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Question 62834: In one city, the probability that a person will pass his or her driving test on the first attempt is 0.67. 11 people are selected at random from among those taking their driving test for the first time. What is the probability that among these 11 people, the number passing the test is between 2 and 4 inclusive?
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Question 62857: A company manufactures calculators in batches of 64 and there is a 4% rate of defects. Find the probability od getting exactly three defects in a batch.
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Question 62858: A family has five children. The probablilty of having a girl is 1/2. What is the probability of having no more than 3 boys?
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Question 62861: Two fair dice are rolled. Find the probability that the sum of the two numbers is not greater than 5.
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Question 62860: If the probability that an identified hurricane will make a direct hit on a certain stretch of beach is 0.20, what are the odds against a direct hit?
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Question 62859: An airline estimates that 95% of the people booked on their flights actually show up. If the airline books 62 people on a flight for which the maximum number is 60, what is the probability that the number of people who show up will exceed the capacity of the plane?
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Question 62856: A multiple choice test has 30 questions. Each question has five possible answers, of which one is correct. If a student guesses on every question, find the probability of getting exactly 12 correct.
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Question 62836: Find the expected number of girls in a family of 7.
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Question 62832: In January in a certain city the unconditional probability of rain on any given day of the month is 0.400. But the probability of rain on a day that follows a rainy day is 0.600 and the probability of rain on a day following a nonrainy day is 0.250. Find the probability that January 1st and January 2nd are rainy and that January 3rd and 4th are not rainy given that December 31st was clear all day.
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Question 62823: How could nonparametric data be transformed into parametric data that could be used in an ANOVA? How do the fe and fo in a nonparametric test correspond to the SSE and the SSA in an ANOVA?
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Question 63255: Data obtained from a test of Nicorette gum a chewing gum to help smokers
If two different subjects are randomly sedected, without replacement find the probability that they are both from the placebo group.
mouth or throat soreness Nicorette (41) placebo (35)
no mouth or throat soreness Nicorette (109) placebo (118)
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Question 63314: Major help needed in figuring this one out? Respectfully thank you for your help!

What is the difference between an independent and a dependent variable? Can independent and dependent variables be interchangeable? Why or why not? Provide an example of this use.

For example, cost accountant Linda Thomas provided the following sampling data for observations obtained during an investigation of the relationship between the volume of an ingredient X and the weight of a production batch Y.

Volume X. Weight Y

10 61

24 110

13 75

7 47

9 78

25 102

6 38

10 42

16 75

15 91

Note: When submitting this question the columns all come together. There are two columns going down but they don't seem to line up when submitting the question.

1) determine the estimated regression equation
2) compute, for batch weight, (a) the sample standard deviation and (b) the standard error of the estimate. Does a comparison of these two values indicate that the regression line would be useful in predicting batch weight? Why or why not?

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Question 63356: For the functions f(x) = 8x2 - 6
and g(x) = -2x2 + 2,
find g(f((-3)). (Do NOT put commas in large numbers.)
For the functions f(x) = 4x + 7 and g(x) = -9x + 11,
find f(g(0)).
For the functions f(x) = 7x2 - 1
and g(x) = -4x2 + 7,
find f(g(-3)). (Do NOT put commas in large numbers.)
For the functions f(x) = 9x + 8 and g(x) = -11x + 9,
find g(f((-4)).
For the functions f(x) = 10x + 11 and g(x) = -5x + 6,
find f(g(-1)).

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Question 63330: Thank your for your continued guidence and help in my pursuit of understanding statistics. Your help is greatly appreciated!
1. The manager of a computer software company wishes to study the number of hours senior executives spend at their desktop computers by type of industry. The manager selected a sample of five executives from each of three industries. At the .05 significance level, can she conclude there is a difference in the mean number of hours spent per week by industry?
Banking Retail Insurance
12 8 10

10 8 8

10 6 6

12 8 8

10 10 10
Note: When submitting all numbers are bunched together but follow underneath each category of Banking, Retail and Insurance.
2. Given the following sample information, test the hypothesis that the treatment means are equal at the .05 significance level.
Treatment 1 Treatment 2 Treatment 3
8 3 3

11 2 4

10 1 5

3 4
2
Note: When submitting all number are bunched together but the firt three columns should go under Treat 1, Treat 2, Treat 3. Columnes 4 should have 3 under Treat 2 and 4 under Treat 3. Column 5 should have 2 under Treat 2.
a.State the null hypothesis and the alternate hypothesis.
b.What is the decision rule?
c.Compute SST, SSE, and SS total.
d.Complete an ANOVA table.
e.State your decision regarding the null hypothesis.

3. The chief of security for the Mall of the Dakotas was directed to study the problem of missing goods. He selected a sample of 100 boxes that had been tampered with and ascertained that for 60 of the boxes the missing pants, shoes, and so on were attributed to shoplifting. For 30 other boxes employees had stolen the goods, and for the remaining 10 boxes he blamed poor inventory control. In his report to the mall management, can he say that shoplifting is twice as likely to be the cause of the loss as compared with either employee theft or poor inventory control and that employee theft and poor inventory control are equally likely? Use the .02 significance level.
4. In a particular market there are three commercial television stations, each with its own evening news program from 6:00 to 6:30 P.M.According to a report in this morning's local newspaper, a random sample of 150 viewers last night revealed 53 watched the news on WNAE (channel 5), 64 watched on WRRN (channel 11), and 33 on WSPD (channel 13). At the .05 significance level, is there a difference in the proportion of viewers watching the three channels?

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Question 61163: An advertising executive receives an average of 10 telephone calls each afternoon between 2 and 4 P.M. The calls occur randomly and independently of one another and follow a Poisson model.
a) Find the probability that the executive will receive 13 calls between 2 and 4 P.M. on a particular afternoon.
b) Find the probability that the executive will receive seven calls between 2 and 3 P.M. on a particular afternoon.
c) Find the probability that the executive will receive at least five calls between 2 and 4 P.M. on a particular afternoon.
d) Find the probability that the executive will receive three or less calls between 2 and 3 P.M. on a particular afternoon.
e) Find the probability that the executive will receive eight or more calls between 2 and 4 P.M. on a particular afternoon.
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Question 60878: can u please help me in this
let E(x^r) = 1/r+1 , r=1,2,3,… find the series representation for the moment generating function of x , sum this series
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Question 60877: can u please help me in this
find the mean and variance if they exist , of each of the following distribution
f(x) = 3 factorial/xfactorial(3-x)factorial * (1/2)^3 , x = 0,1,2,3 zero else where

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Question 60612: please help me in this
let f(X) =2x 0 a) compute E(1/x)
b) find distribution function and the p.d.f of Y=1/X
c) compute E(y) and compare this result with the answer obtained in part a

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Question 60610: please help me in this
let x have the p.d.f f(x)=3x^2 , 0
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Question 60607: please help me in this
let x have the p.d.f f(x)= (x+2)/18 , -2 find E[(x+2)^3], and E[6x-2(x+2)^3]
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Question 60605: please help me in this
p(c1 intersect c2 intersect c3 intersect c4 )= p(c1)p(c2|c1)p(c3|c1 intersect c2)p(c4|c1intersect c2 intersect c3)
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Question 60602: i need help in this

if x is arandom variable such that
E(x) = 3 and E(x^2)=13 ,
use techybeshev’s inequality to determine
alower bound for the probability p(-2
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Question 60599: i need help in this

let E(x^r) = 1/r+1 , r=1,2,3,… find the series representation for the moment generating function of x , sum this series
let E(x^r) = 1/r+1 , r=1,2,3,… find the series representation for the moment generating function of x , sum this series
Click here to see answer by stanbon(57214)

Question 60217: Several students are unprepared for a true/false test with 50 questions, and all of their answers are guesses. Find the mean, variance and standard deviation for the number of correct answers for such students. For mean and variance give 1 decimal place of precision, for standard deviation give 2. give the values, separated by commas, with 1 blank character between a comma and subsequent value.
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Question 60597: i want your help please :
find the mean and variance if they exist , of each of the following distribution
f(x) = 3!/x!(3-x)!*(1/2)^3 , x = 0,1,2,3 zero else where

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Question 60416: please i need your help
abowl contain 10 chips, of which 8 are marked $ 2 each and 2 are marke $5 each, let aperson choose at random and without replcement , 3 chips from this bowl, if the person is to receive the sum of the resulting amount
find his expectation

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Question 60412: Statistics are like speaking or reading a foreign language unlike any other. Thank you for your patience and support.
1. In hypothesis testing why are verbal problem statements converted to numerical problem statements?
2. Why is it important to identify the parameter when converting a problem statement from the verbal numerical?
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Question 60220: A statistics professor finds that when she schedules an office hour for student help, an average of two students arrive. fidn the probability that in a randomly selected office hour, the number of student arrivals is five. give the answer as a decimal value with 4 places of precision, and no leading 0.
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Question 60050: Can somebody explain how should I deal with this? I pulled about a handful of hair and I still don't know what to do.
The skid properties of a snow tire have been tested and a mean skid distance of 154 feet has been established for standardized conditions. A new more , expensive tire is developed, but test on a sample of 17 new tires will be purchased only if it can be shown(at the 0.05 sifnificance level) that they skid less than the current tires.Based on the sample, will the new tires be purchased? Indicate whether you would use a z score or t score, give the value of that score and the critical value to 2 decimal places, and state whether you "Reject" or "Fail to reject the null hyphotesis.

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Question 60219: A statistics professor finds that when she schedules an office hour for student help, an average of two students arrive. fidn the probability that in a randomly selected office hour, the number of student arrivals is five. give the answer as a decimal value with 4 places of precision, and no leading 0.
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Question 60215: The Newman Constuction Comapany bids on a job to constuct a building>. If the bid is won, there is a 0.7 proability of making a $175,000 profit and there is a probability of 0.3 that the contractor will break even. what is the expected value? Use standard (u.s.) monetary format, with no blank between the $ sign and the value.
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Question 60214: the Kwik Klean Car Wash loses $30 on rainy days and gains $120 on days when it does not rain. If the probability of rain is 0.15, what is the expected value of net profit? Use standard (U.S.) monetary format, with no blank between the $ sign and the value.
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Question 60197: please help me in this
if x has the variance sigma^2 , then var[ax+b]=a^2 var(X)=a^2 sigma^2
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Question 60196: please help me in this
if the pdf of the contiuos random variable is given by
f(x) = 630 x^4(1-x)^4 0 0 otherwise

find the probability that x will take on avalue within 2 standard diviation of the mean and compare it with lower bound provided by tchebyshev's theorom
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3871..3915, 3916..3960, 3961..4005, 4006..4050, 4051..4095, 4096..4140, 4141..4185, 4186..4230, 4231..4275, 4276..4320, 4321..4365, 4366..4410, 4411..4455, 4456..4500, 4501..4545, 4546..4590, 4591..4635, 4636..4680, 4681..4725, 4726..4770, 4771..4815, 4816..4860, 4861..4905, 4906..4950, 4951..4995, 4996..5040, 5041..5085, 5086..5130, 5131..5175, 5176..5220, 5221..5265, 5266..5310, 5311..5355, 5356..5400, 5401..5445, 5446..5490, 5491..5535, 5536..5580, 5581..5625, 5626..5670, 5671..5715, 5716..5760, 5761..5805, 5806..5850, 5851..5895, 5896..5940, 5941..5985, 5986..6030, 6031..6075, 6076..6120, 6121..6165, 6166..6210, 6211..6255, 6256..6300, 6301..6345, 6346..6390, 6391..6435, 6436..6480, 6481..6525, 6526..6570, 6571..6615, 6616..6660, 6661..6705, 6706..6750, 6751..6795, 6796..6840, 6841..6885, 6886..6930, 6931..6975, 6976..7020, 7021..7065, 7066..7110, 7111..7155, 7156..7200, 7201..7245, 7246..7290, 7291..7335, 7336..7380, 7381..7425, 7426..7470, 7471..7515, 7516..7560, 7561..7605, 7606..7650, 7651..7695, 7696..7740, 7741..7785, 7786..7830, 7831..7875, 7876..7920, 7921..7965, 7966..8010, 8011..8055, 8056..8100, 8101..8145, 8146..8190, 8191..8235, 8236..8280, 8281..8325, 8326..8370, 8371..8415, 8416..8460, 8461..8505, 8506..8550, 8551..8595, 8596..8640, 8641..8685, 8686..8730, 8731..8775, 8776..8820, 8821..8865, 8866..8910, 8911..8955, 8956..9000, 9001..9045, 9046..9090, 9091..9135, 9136..9180, 9181..9225, 9226..9270, 9271..9315, 9316..9360, 9361..9405, 9406..9450, 9451..9495, 9496..9540, 9541..9585, 9586..9630, 9631..9675, 9676..9720, 9721..9765, 9766..9810, 9811..9855, 9856..9900, 9901..9945, 9946..9990, 9991..10035, 10036..10080, 10081..10125, 10126..10170, 10171..10215, 10216..10260, 10261..10305, 10306..10350, 10351..10395, 10396..10440, 10441..10485, 10486..10530, 10531..10575, 10576..10620, 10621..10665, 10666..10710, 10711..10755, 10756..10800, 10801..10845, 10846..10890, 10891..10935, 10936..10980, 10981..11025, 11026..11070, 11071..11115, 11116..11160, 11161..11205, 11206..11250, 11251..11295, 11296..11340, 11341..11385, 11386..11430, 11431..11475, 11476..11520, 11521..11565, 11566..11610, 11611..11655, 11656..11700, 11701..11745, 11746..11790, 11791..11835, 11836..11880, 11881..11925, 11926..11970, 11971..12015, 12016..12060, 12061..12105, 12106..12150, 12151..12195, 12196..12240, 12241..12285, 12286..12330, 12331..12375, 12376..12420, 12421..12465, 12466..12510, 12511..12555, 12556..12600, 12601..12645, 12646..12690, 12691..12735, 12736..12780, 12781..12825, 12826..12870, 12871..12915, 12916..12960, 12961..13005, 13006..13050, 13051..13095, 13096..13140, 13141..13185, 13186..13230, 13231..13275, 13276..13320, 13321..13365, 13366..13410, 13411..13455, 13456..13500, 13501..13545, 13546..13590, 13591..13635, 13636..13680, 13681..13725, 13726..13770, 13771..13815, 13816..13860, 13861..13905, 13906..13950, 13951..13995, 13996..14040, 14041..14085, 14086..14130, 14131..14175, 14176..14220, 14221..14265, 14266..14310, 14311..14355, 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17551..17595, 17596..17640, 17641..17685, 17686..17730, 17731..17775, 17776..17820, 17821..17865, 17866..17910, 17911..17955, 17956..18000, 18001..18045, 18046..18090, 18091..18135, 18136..18180, 18181..18225, 18226..18270, 18271..18315, 18316..18360, 18361..18405, 18406..18450, 18451..18495, 18496..18540, 18541..18585, 18586..18630, 18631..18675, 18676..18720, 18721..18765, 18766..18810, 18811..18855, 18856..18900, 18901..18945, 18946..18990, 18991..19035, 19036..19080, 19081..19125, 19126..19170, 19171..19215, 19216..19260, 19261..19305, 19306..19350, 19351..19395, 19396..19440, 19441..19485, 19486..19530, 19531..19575, 19576..19620, 19621..19665, 19666..19710, 19711..19755, 19756..19800, 19801..19845, 19846..19890, 19891..19935, 19936..19980, 19981..20025, 20026..20070, 20071..20115, 20116..20160, 20161..20205, 20206..20250, 20251..20295, 20296..20340, 20341..20385, 20386..20430, 20431..20475, 20476..20520, 20521..20565, 20566..20610, 20611..20655, 20656..20700, 20701..20745, 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