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Question 268442: A committee is evaluating six equally qualified candidates for a job. only three of the six will be invited for an interview, among the chosen three, the order of invitation is of importance because the first candidate will have the best chance to being accepted, the second will be made an offer only if the committee rejects the first, and the third will be made an offer only if the committee should reject both the first and the second. how many possible ordered choices of three out of six candidates are there?
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Question 268444: Q. In a shipment of 14 computer parts, 3 are faulty and the remaining 11 are in working order. three elements are randomly chosen out of the shipment. what is the probability that all three faulty elements will be the ones chosen?
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Question 268453: A market researcher needs to interview people who drive to work. in the area where the study is undertaken, 75% of the people who drive to work. if three people agree to be interviewed, what is the probability that at least one satisfies the requirement? what is the necessary assumption, and how does it apply?
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Question 268452: 18) An analysis of variance (ANOVA) tests population variance.
A.

True
B.

False

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Question 268449: 13) If the paired differences are normal in a test of mean differences, the distribution used for testing is the
A.

normal distribution.
B.

student t distribution.
C.

F distribution.
D.

chi-square.

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Question 268446: Q. A company has four departments: manufacturing , distribution, marketing and management. the number of people in each department is 55, 30, 21 and 13 respectively. Each department is expected to send one representative to a meeting with the company president. how many possible sets of representatives are there?
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Question 268500: Please help solve this problem Write out all of the outcomes for which the sum of the numbers showing is 5. Two standard dice are rolled and the number of dots on the top face of each die is recorded.
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Question 268480: If a sociologist wishes to determine if there is evidence that average family in a community exceeds $47,000, a two-tailed test should be used.

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Question 268505: if roulette were fair, how much should the house pay a player who bets $20 on a single number and it comes up? the odds against winning are 36:1
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Question 268513: A survey of 12 people at a bookstore showed that five had purchased a hardcover book. If seven people are selected at random, what is the probability that four of them had purchased a hardcover book?
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Question 268464: Given that you have a mean of 100 and standard deviation of 3; if repeated samples of 36 were selected what proportion of them would have means less than 99 and greater than 100?
I have tried to solve this using central limit therom and end up with
-1/(3/6) = -1/0.5 = -0.5 however the book states that
SE with n=36 is 3/6 The critical ratio for a mean equal to 99 is (99-100)/0.5=-2.00 and for 101 is +2.00
I do not understand the critical ration portion...if you solve the equation the answer is -0.5 not -2.00...where am I going wrong?

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Question 268152: High levels of cockpit noise in an aircraft can damage the hearing of pilots who are exposed to this
hazard for many hours. A Boeing 727 co-pilot collected 61 noise observations using a handheld
sound meter. Noise level is defined as “Low” (under 88 decibels), “Medium” (88 to 91 decibels),or “High” (92 decibels or more). There are three flight phases (Climb, Cruise, Descent). Research
question: At α = .05, is the cockpit noise level independent of flight phase? (Data are from
Capt. Robert E. Hartl, retired.)
Noise Level Climb Cruise Descent Row Total
Low 6 2 6 14
Medium 18 3 8 29
High 1 3 14 18
Col Total 25 8 28 61
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Question 268618: If Punxsutawney Phil sees his shadow on the first Monday in February, then legend says that winter
will last 6 more weeks. In 118 years, Phil has seen his shadow 104 times. (a) What is the probability
that Phil will see his shadow on a randomly chosen Groundhog Day? (b) What kind of
probability is this? (Data are from www.groundhog.org.)

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Question 268377: A license plate is to have five uppercase letters or digits. Determine the number of license plates possible of repetition is permitted and if any position can contain either a letter or digit with the exception that the first position cannot contain the letter o or the number 0
Click here to see answer by Alan3354(30983)

Question 268642: suppose you roll one six sided die and one four sided die.
what is the probability that you will get a sum less than 5?
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Question 268668: I need help with this probability problem.
Suppose that 19% of the employees of a given corporation utilize the company fitness center during the lunch hour. Moreover, assume that 58% of all employees are male, and 13% of all employees are males who utilize the company fitness center during the lunch hour.
A) If we choose an employee at random from this corporation, what is the probability that this person is a female?
B) If we choose an employee at random from this corporation, what is the probability that this person is a male or someone who utilizes the company fitness center during the lunch hour?
Click here to see answer by stanbon(57250)

Question 268712: Im stuck on this problem.
A major airline company is concerned that its proportion of late arrivals has increased from the historical level of 18%. The test the hypothesis, Ho: pie<= 0.18 vs H1: pie>.18 the airline takes a random sample of 1240 flights and finds 310 arrived late. What is the test statistic?
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Question 268772: 7. A flashlight has 6 batteries, 2 of which are defective. If 2 are selected at random without replacement, find the probability that both are defective.
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Question 268752: a box contains 8 red chips, 6 blue chips, and 12 white chips. three chips are randomly drawn from the box and not replaced. find the probability of drawing a red then a white then a blue chip.
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Question 268797: If North American casino roulette were fair, how much should it pay to a player who bets $10 on red and a red number comes up? The odds against winning a bet on a red in roulette are 1.01 to 1.

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Question 268868: a certain operation on a time- shared computer takes anywhere from 1/100 to 4/100 of a second, and the operation time is no more likely to be in any sub interval in this range than it is to be in any other sub interval of the same length. what is the probability that the operation will take over 2/100 of a second?
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Question 268899: one card is selected from a deck of playing cards. Determine the probability of selecting “a jack or a club
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Question 268918: In the 108th Congress, the Senate consists of 51 Republicans, 48 Democrats, and 1 independant. If a lobbyist for the tobacco industry randomly selects 3 different Senators, what is the probability that they are all Republicans? Would a lobbyist by likely to use random selection in this situation?
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Question 268871: a financial analyst believes that if interest rate decrease in a given period, then the probability that the stock market will go up is 0.80. the analyst further believes that interest rates have a 0.40 chance of decreasing during the period in question. given the above information, what is the probability that the market will go up and interest rate go down during the period in question.
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Question 268990: In a 30-person group, there are 3 doctors, 5 lawyers, and 4 teachers. What is the probability of selecting a 3-person group composed of all teachers? (no replacement) What are the odds of selecting such a group?
Click here to see answer by drk(1908)

Question 268993: You are running an ice-cream place. You have 15 different flavors. You want to make it sound like more, so you want to advertise the number of double-decker ice-cream cones you can make. If you repeat flavors, how many possible different cones could you make?
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Question 269015: a couple has 4 children find the probability 3 are girls
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Question 269117: Can someone please help with this question?
Determine the correct critical value(s) in each of the following situations. You may assume data sets are normally distributed.
A two-tailed test with alpha = 0.025. You may assume the value of alpha is known.
A left-tailed test with alpha = 0.10, unknown alpha, and a sample of size 35. You may assume the data is normally distributed.

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Question 269124: a standard six faced die and a standard four-faced die are both rolled once the cube’s faces are numbered 1-6 and the tetrahedron ‘s faces are numbered 1-4 what is the probability that the sum of the downward – facing faces is grater than 6 ?
Click here to see answer by AnlytcPhil(1276)

Question 269008: the depth of fluid,H cm, in a vessel at time t minutes is given by
H = 16+4t+2t^2-(t^3/16)
determine the rate at which the depth is changing after 4 minutes.
if the cross section of the vessel is circular,of diameter 2 m, determine the rate of filling in m3 min-1,at this time.
Click here to see answer by scott8148(6628)

Question 269148: I don't quite understand this and need help, please.
A cereal company claims that the mean weight of the cereal in its packets is at least 14 oz. The weights (in ounces) of the cereal in a random sample of 8 of its cereal packets are listed below.
14.6 13.8 14.1 13.7 14.0 14.4 13.6 14.2
At the 0.01 significance level, does the sample support the company’s claim that the mean weight is at least 14 ounces? You may assume the weight of cereal packets is normally distributed.

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Question 269149: I need help with this question, please.
Various temperature measurements are recorded at different times for a particular city. The mean of 21°C is obtained for 32 temperatures on 32 different days. Assuming that σ = 1.5°C, test the claim that the population mean is actually less than 22°C. Use a 0.05 significance level.
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Question 269147: Please help answer the following question. Thank you.
In tests of a computer component, it is found that the mean time between failures is 520 hours. A modification is made which is supposed to increase the time between failures. Tests on a random sample of 10 modified components resulted in the following times (in hours) between failures.
518 548 561 523 536
499 538 557 528 563
a. Find x-bar and s for this data set.
b. At the 5% significance level, test the claim that for the modified components, the mean time between failures is greater than 520 hours? You may assume the times between failures are normally distributed. Use the traditional method to make your decision.
Click here to see answer by stanbon(57250)

Question 269173: A real estate agent makes $18,000. Her commission is 3%. How many homes must she sell to earn $65,000. I think to start this problem I need to divide 3% into $65,000.
Click here to see answer by josmiceli(9661)

Question 269217: A machine produces 9 inch latex gloves. A sample of 51 gloves is selected, and it is found that 46 are shorter than they should be. Find the 98% confidence interval on the proportion of all such gloves that are shorter than 9 inches.

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Question 269139: An examination consists of 10 multiple choice questions, each with 5 choices, 1 is correct and 4 incorrect. How many ways can a student mark the answers to these questions marking all 10 questions incorrectly?
Click here to see answer by dabanfield(803)

Question 269246: A machine produces 3-inch nails. A sample of 12 nails was selected and their lengths determined. The results are as follows:
2.97 2.86 2.82 2.86 2.95 2.80 2.81 2.98 2.88 2.83 2.95 2.95
Assuming that = 0.01, test the hypothesis that the population mean is equal to 3.
· State the null and alternate hypotheses
· Calculate the mean and standard deviation
· Determine which test statistic applies, and calculate it
· Determine the critical value(s).
· State your decision: Should the null hypothesis be rejected?

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Question 269290: A random sample of 51 observations was selected from a normally distributed population. The sample mean was xbar = 64, and the sample variance was s2 = 48.0. Does the sample show sufficient reason to conclude that the population standard deviation is not equal to 9 at the 0.02 level of significance? Use the p-value method.
· State the null and alternate hypotheses
· Determine which test statistic applies, and calculate it
· Determine the corresponding probability, and compare to
· State your decision: Should the null hypothesis be rejected?
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Question 269314: For a trip a travelerpacked 3 pairs of pants, 11 shirts, and 5 pairs of shoes. How many outfits can he wear?
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Question 269317: In how many ways can 9 instructors be assigned to 9 sections of a course in mathematics?
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Question 269316: In how many different ways can the top ten new indie bands be ranked on a top ten list? The top song for each of the ten bands will compete to receive monetary awards of $1000, $500, $250, $100, respectively. In how many ways can the awards be given?
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Question 269315:
An insurance company states that 75% of its claims are settled within 5 weeks. A consumer group selected a random sample of 25 of the company’s claims and found 8 of the claims were settled within 5 weeks. Is there enough evidence to support the consumer group’s claim that fewer than 75% of the claims were settled within 5 weeks? Test using the traditional approach with α = 0.05.
· State the null and alternate hypotheses
· Calculate the sample proportion
· Determine which test statistic applies, and calculate it
· Determine the critical value(s).
· State your decision: Should the null hypothesis be rejected?

Click here to see answer by stanbon(57250)

Question 269429: A bag of marbles contains 7 red, 3 blue, 5 white, 3 green.
A. P(red, red, white) with replacement
B.P(red, red, white) without replacement
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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, 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, 14356..14400, 14401..14445, 14446..14490, 14491..14535, 14536..14580, 14581..14625, 14626..14670, 14671..14715, 14716..14760, 14761..14805, 14806..14850, 14851..14895, 14896..14940, 14941..14985, 14986..15030, 15031..15075, 15076..15120, 15121..15165, 15166..15210, 15211..15255, 15256..15300, 15301..15345, 15346..15390, 15391..15435, 15436..15480, 15481..15525, 15526..15570, 15571..15615, 15616..15660, 15661..15705, 15706..15750, 15751..15795, 15796..15840, 15841..15885, 15886..15930, 15931..15975, 15976..16020, 16021..16065, 16066..16110, 16111..16155, 16156..16200, 16201..16245, 16246..16290, 16291..16335, 16336..16380, 16381..16425, 16426..16470, 16471..16515, 16516..16560, 16561..16605, 16606..16650, 16651..16695, 16696..16740, 16741..16785, 16786..16830, 16831..16875, 16876..16920, 16921..16965, 16966..17010, 17011..17055, 17056..17100, 17101..17145, 17146..17190, 17191..17235, 17236..17280, 17281..17325, 17326..17370, 17371..17415, 17416..17460, 17461..17505, 17506..17550, 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, 20746..20790, 20791..20835, 20836..20880, 20881..20925, 20926..20970, 20971..21015, 21016..21060, 21061..21105, 21106..21150, 21151..21195