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Question 350926: Hello!
the communication network has built-in a safeguard system against failures. In this system if Line 1 fails, it is bypassed and Line 2 is used. If line 2 also fails, it is bypassed and Line 3 is used. The proabability of the failure of any one of these 3 lines is 0.01, and the failures of these lines are independent events. What is the proability that this system of 3 lines does not completely fail?
Thank You
Click here to see answer by Fombitz(13828)

Question 350994: An ordinary (fair) die is a cube with the numbers through on the sides (represented by painted spots). Imagine that such a die is rolled twice in succession and that the face values of the two rolls are added together. This sum is recorded as the outcome of a single trial of a random experiment.
Compute the probability of each of the following events:
Event : The sum is greater than 9 .
Event : The sum is not divisible by 2 and not divisible by 3 .
Click here to see answer by edjones(7569)

Question 350992: Die rolling
An ordinary (fair) die is a cube with the numbers through on the sides (represented by painted spots). Imagine that such a die is rolled twice in succession and that the face values of the two rolls are added together. This sum is recorded as the outcome of a single trial of a random experiment.
Compute the probability of each of the following events:
Event : The sum is greater than 7 .
Event : The sum is divisible by 6.
Click here to see answer by edjones(7569)

Question 349882: Twenty tires are tested to see if they last as long as they claim they do. Three tire fail the test. Two tires are selected at random without replacement for a detained inspection.
A. Find the probability that both tires failed the test.
B. Find the probability that both tires passed the test.
C. Find the probability that at least one of the tire passed the test.
Click here to see answer by sudhanshu_kmr(1152)

Question 345970: Suppose that there are 55 democrats and 45 republicans in the U.S. Senate.
A committee of seveen senators is to be formed by selecting members of the senate randomly.
A) what is the probability that the committee is composed of all democrats?
B) What is the probility the committe is composed of all republicans?
C) What is the probability that the committee is composed of three democrats and four republicans?
Click here to see answer by sudhanshu_kmr(1152)

Question 351167: A state lottery game uses ping pong balls numbered 0-39. Balls with the numbers 20,8,7, and 1 have been selected already.
Find the probability of drawing a ball with a number less than 10 as the fifth ball.
I believe the answer could be:
10 over 36 is that correct? do you need to simplify?
Click here to see answer by scott8148(6628)

Question 351216: I am having trouble solving for values within the t value equation when solving for your test statistic:
x = sample mean
m= Population mean
se = Standard error
x-m/se=t
I am solving for m
2.49 - m/.0236=t

Click here to see answer by stanbon(57940)

Question 351196: Find the probability of a couple having a baby girl when their sixth child is born, given that the first five children were all girls. Assume boys and girls are equally likely.
Click here to see answer by sudhanshu_kmr(1152)

Question 351343: If there are 14 boys and 11 girls in a room what would be the probability of my randomly selecting a girl/
Click here to see answer by jim_thompson5910(28696)

Question 351381: A bag containing 5 red balls, 3 blue balls and 2 yellow balls. A ball is drawn and not replaced. A second ball is drawn. Find the probabilty of drawing:
a) Two red balls
b) One blue ball and one yellow ball
c) Two yellow balls
d) A red ball and a blue ball
Click here to see answer by jim_thompson5910(28696)

Question 351386: A card is drawn and a die is thrown. Find the following probabilities:
a) Drawing a spade and rolling a four
b) Rolling an odd number and drawing an odd numbered card
c) Rolling a factor of 12 and drawing a card that is a factor of twelve (exclude 1 in both cases)
Click here to see answer by jim_thompson5910(28696)

Question 351398: A parent- teacher committee consisting of 4 people is to be formed from 20 parents and 5 teachers. Find the probability that the committee will consist of these people. (assume that the selection will be random).
a. all teachers
b. 2 teachers and 2 parents
c. all parents
d. 1 teacher and 3 parents
Click here to see answer by solver91311(17059)

Question 351370: A recent study reports that 2.5% of elementary children are allergic to peanuts. A random sample of 200 elementary school children is collected to test this.
Compute the probability that proportion of children in the sample of 200 who are allergic to peanuts is 3% or less.
Click here to see answer by stanbon(57940)

Question 351503: Drawing fro, a regular deck of playing cards, what is the probability of drawing a face card (jack, queen, king) 3 times in a row? (Assume that jokers are taken out and assume no replacement).
Click here to see answer by Fombitz(13828)

Question 351506: Let's say you have a bag that contains 10 colored beads. You can pull out one bead at a time and then put it back and then shake up the bag. Let's say you have done this five times and have pulled out a red bead three times, a blue bead, and a green bead. What are the facts and what inferences do you have about the contents of the bag?
Click here to see answer by stanbon(57940)

Question 351496: An exam consists of 50 multiple choice questions. Based on how much you studied, for any given question, you think you have a probability of 0.64 of getting the correct answer. Consider the sampling distribution of the sample proportion of correct questions out of 50.
Find the mean and standard error of the sampling distribution of this proportion.
Click here to see answer by stanbon(57940)

Question 351450: Half of a set of the parts are manufactured by machine A and half by machine B. Six percent of all the parts are defective. Eight percent of the parts manufactured on machine A are defective.
Click here to see answer by stanbon(57940)

Question 351702: There are five chemistry instructors and six physics instructors at a college. If a committee of four instructors is selected, find the probability that at least one of them is a physics instructor. Express your answer as a fraction in lowest terms.
I keep trying to multiply 5/11^4 and then subtracting from one and I cant get the answer. I am so confused.

Also, this problem:If three cards are drawn from a deck and not replaced, find the probability of getting at least one spade. Express your answer as a fraction in lowest terms.
I tried multiplying 39/52^3 and then subtracting from 1 but thats not it either and I have to have both of these in fraction form.
Click here to see answer by stanbon(57940)

Question 351684: describe whether the following study would most likely be "observational" or experimental" and why would it be so.

Researchers assign one group of students to a classroom on ground and another an online classroom to determine achievement differences.

Click here to see answer by stanbon(57940)

Question 351786: The English Premier League consists of 20 teams. Tottenham is currently in 8th place on the table. It has 20% chance of winning and 50% chance of losing against any team placed above it. If a team is placed below it, Tottenham has a 50% chance of of winning and 30% chance of losing. Find the probability that Tottenham will draw its next game.
Thanks A Million in Advance ! :)
Click here to see answer by scott8148(6628)

Question 344831: An airport limousine can accommodate up to 4 passengers on any trip. The company will accept a maximum of 6 reservations for a trip and a passenger must have a reservation. From previous records, 45% of those making reservations do not appear for the trip.
a) If 6 reservations are made, what is the probability that at least 1 person cannot be accommodated on the trip?

b) If 6 reservations are made, what is the expected number of available places when the limousine departs?
c) Suppose the probability distribution of the number of reservations made is given in the accompanying table.
Number of reservations 3 4 5 6
Probability 0.1 0.2 0.3 0.4
Let X denote the number of passengers on a randomly selected trip. Obtain the probability mass function of X.
Click here to see answer by donrys(1)

Question 351943: Approximately 79% of all marketing personnel are extroverts, whereas about 64% of all computer programmers are introverts.
(a) At a meeting of 14 marketing personnel, what is the probability that 9 or more are extroverts? (Use 3 decimal places.)

What is the probability that 4 or more are extroverts? (Use 3 decimal places.)

What is the probability that all extroverts? (Use 3 decimal places.)

(b) In a group of 6 computer programmers, what is the probability that none are introverts? (Use 3 decimal places.)

What is the probability that 4 or more are introverts? (Use 3 decimal places.)

What is the probability that all are introverts? (Use 3 decimal places.)

Click here to see answer by jrfrunner(365)

Question 352011: a card is drawn from a deck of 10 cards numbered 1 thru 10 and a number cube is rolled. find the probability (10 and 3)
Click here to see answer by edjones(7569)

Question 352088: The following table shows the observed distribution of A, B, AB, and O blood types in three samples of African Americans living in different locations.
Test at the α = 0.05 level of significance, whether the distribution of blood type for African Americans is different across the three regions.
I(Florida) II(Iowa) III(Missouri)
A 122 1781 353
B 117 1351 269
AB 19 289 60
O 244 3301 713

Click here to see answer by stanbon(57940)

Question 352085: I would like to know if I did the problem correctly:
Percentage of adults who drink alcohol. Of the 1516 adults interviewed, 985 said that they drank.
a. Determine a 95% confidnce interval for the proportion, p, of all Americans who drink alcohol.
b. Interpret results.
This is what I came up with:
N=1516, x=985 and n-x=531 Both x and n-x are at least 5
985/1516=0.6497; za/2=z0.025=1.96
(a) 0.6497-1.96sqrt0.6497(1-0.6497)/1516 to 0.6497+1.96sqrt0.6497
)/1516=6.35,0079
(b) we can be 95% confident that the proprotion of adults who drink alcohol is somewhere between those numbers.
Thank you for any help you can give me.
Click here to see answer by stanbon(57940)

Question 352003: Could someone Please help, I need a sketch of this problem. Showing the comparison distribution, cutoff(or cutoffs) and score of the sample on this distribution. Thank you
hull hypothesis H): μ≤35, H1: alternative hypothesis H1: μ>35
significant level is 0.01
z-score is (58-35)/10 = 2.3
p-value is 0.0107

Click here to see answer by stanbon(57940)

Question 352149: You roll a red die and a green die. What is the size of the sample space of all possible outcomes or rolling these two dice, given that the red die show an odd prime number and the green die shows an even number? .23
Click here to see answer by ulidelri94@yahoo.com(1)

Question 352141: a card is taken at random from a pack of cards and replaced. A second card is drawn. The probability of a diamond being drawn is one quarter. What is the probability that both cards are from different suits?
Click here to see answer by stanbon(57940)

Question 352140: a card is taken at random from a pack of cards and replaced. A second card is drawn. The probability of a diamond being drawn is one quarter. What is the probability that both cards are from the same suit?
Click here to see answer by stanbon(57940)

Question 352139: a card is taken at random from a pack of cards and replaced. A second card is drawn. The probability of a diamond being drawn is one quarter. What is the probability that at least one card is a diamond?
Click here to see answer by stanbon(57940)

Question 352126: There is a committee of 4 people. There are 5 teachers and 20 parents to choose for this committee. What is the probability that:
A: All are teachers?
B: Two are teachers and two are parents?
Click here to see answer by ewatrrr(10682)

Question 352137: 3. A glass jar contains 6 red, 5 green, 8 blue and 3 yellow marbles. If a single marble is chosen at random from the jar, what is the probability of choosing a red marble? a green marble? a blue marble? a yellow marble?

Click here to see answer by ewatrrr(10682)

Question 352138: a card is taken at random from a pack of cards and replaced. A second card is drawn. The probability of a diamond being drawn is one quarter. What is the probability that exactly one card is a diamond?
Click here to see answer by ewatrrr(10682)

Question 352210: Find the mean, variance, and standard deviation for the following probability distribution.
X= 3 6 9 12 15
Px=.15 .29 .30 .11 .15
I know to get the mean you multiply for example 3 x .15, 6 x .29, 9 x .30, and so on. But when I am crunching my numbers to try to get the standard deviation and variance, they are not coming out.
I really appreciate the help! =)
Click here to see answer by Fombitz(13828)

Question 352205: 1. An urn contains 15 marbles – 8 blue, 5 red, and 2 white. If 2 marbles are chosen without replacement, find the probability that the first marble is blue and the second is white.
2. A quick quiz consists of a true/false question followed by a multiple-choice question with four possible answers (a,b,c,d). An unprepared student makes random guesses for both answers. What is the probability that s/he gets both answers correct?

Click here to see answer by Fombitz(13828)

Question 352387: Suppose a jar contains four balls labeled 1, 2, 3, and 4. A second jar contains five balls, labeled 1, 2, 3, 4, and 5. An experiment consists of taking one ball from the first jar, and then taking a ball from the second jar. How many outcomes will make up the sample space for this experiment? Provide some outcome examples for this experiment.
Click here to see answer by edjones(7569)

Question 352393: Given 32 flavors of ice cream, how many arrangements are possible on a double scoop cone? How many on a triple scoop cone? What is the probability of getting a triple scoop of the same flavor? Explain the reasoning used to obtain the answers to the previous questions.
Click here to see answer by edjones(7569)

Question 352565: there were 200 raffle tickets sold. Jewel bought one ticket. What is her chance of winning expressed as a percent?
Click here to see answer by josmiceli(9817)

Question 352391: Consider the following scenario: Marbles are drawn without replacement from a bag of 15 marbles.

•How many samples of 3 marbles can be drawn?
•How many samples of 3 marbles can be drawn if they are drawn with replacement?
•Explain the reasoning used to obtain the answers to the above questions.

Click here to see answer by stanbon(57940)

Question 352368: The amount of fill in a half liter soft drink bottle is normally distributed. The process has a std. deviation of 5 ml. The mean is adjustable. a) Where should the mean be set to ensure a 95 percent probability that a half liter bottle will not be underfilled? b) A 99 percent probability? c) A 99.9 percent probability? Explain.

Click here to see answer by stanbon(57940)

Older solutions: 1..45, 46..90, 91..135, 136..180, 181..225, 226..270, 271..315, 316..360, 361..405, 406..450, 451..495, 496..540, 541..585, 586..630, 631..675, 676..720, 721..765, 766..810, 811..855, 856..900, 901..945, 946..990, 991..1035, 1036..1080, 1081..1125, 1126..1170, 1171..1215, 1216..1260, 1261..1305, 1306..1350, 1351..1395, 1396..1440, 1441..1485, 1486..1530, 1531..1575, 1576..1620, 1621..1665, 1666..1710, 1711..1755, 1756..1800, 1801..1845, 1846..1890, 1891..1935, 1936..1980, 1981..2025, 2026..2070, 2071..2115, 2116..2160, 2161..2205, 2206..2250, 2251..2295, 2296..2340, 2341..2385, 2386..2430, 2431..2475, 2476..2520, 2521..2565, 2566..2610, 2611..2655, 2656..2700, 2701..2745, 2746..2790, 2791..2835, 2836..2880, 2881..2925, 2926..2970, 2971..3015, 3016..3060, 3061..3105, 3106..3150, 3151..3195, 3196..3240, 3241..3285, 3286..3330, 3331..3375, 3376..3420, 3421..3465, 3466..3510, 3511..3555, 3556..3600, 3601..3645, 3646..3690, 3691..3735, 3736..3780, 3781..3825, 3826..3870, 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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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