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Question 318955: Can anyone help me with this probability question? A box has the following six letters: R A N D O M . What is the probability of the outcome D A N in that order if three letters are drawn one by one 1)with replacement 2) without replacement? I could make a chart or tree if there were only two letters but I'm not sure how to solve with three. I know I've got one in six chances to pull individual letters, but I'm not sure how to work the other factors in. Any help would be appreciated!
Click here to see answer by stanbon(57347)

Question 318931: I am doing a homework problem:
farmers often sell fruits and vegetables at roadside stands during the summer. one such roadside stand has a daily demand for tomatoes that is approximately normally distributed with a mean equal to 133 and standard deviation 30 per day. How many tomatoes must be available on any given day so that there is only a 1.5% chance that all tomatoes will be sold?
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Question 319030: In one town, 54% of all voters are Democrats. If two voters are randomly selected for a survey, find the probability that they are both Democrats. Round to the nearest thousandth if necessary.
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Question 318913: Can someone please help me with this problem?

CitiBank recorded the number of customers to use a downtown ATM during the noon hour on 32 consecutive workdays. (a) Use Excel or MegaStat to find the mean, median, and mode. (b) Do these measures of central tendency agree? Explain. (c) Are the data symmetric or skewed? If skewed, which direction? (d) Note strengths or weaknesses of each statistic of central tendency for
the data.
25 37 23 26 30 40 25 26
39 32 21 26 19 27 32 25
18 26 34 18 31 35 21 33
33 9 16 32 35 42 15 24
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Question 319040: A jar contains 10 red marbles and 30 green ones. How many more red marbles must be added to the jar so that 60% of the marbles will be red?
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Question 319104: it is almost time for the world cup! a soccer team (11 players) is selected from a group of 180 students by choosing at random. what is the probability that you and your four best friends in the group are part of the selected soccer team?

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Question 319112: a box contains 10 red cards numbered 1 through 10. List the sample space of picking one card from the box.
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Question 319081: In New York's Millennium Millions Lottery game, five numbers from 1 to 50 and one number for the Big Millennium Ball from 1 to 30 must be selected. There is one jackpot prize for the ticket with the six numbers that match the six randomly selected numbers. What are the odds against winning the jackpot?

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Question 318891: A production filling operation has a population standard deviation of 6 ounces. When in proper adjustment, the mean filling weight for the production process is 50 ounces. A quality control inspector selects a random sample of 36 containers and finds that the mean weight is 48.6 ounces. Does the process need adjustment? Why? Find the p-value. (Hint: the process will need adjustment if the mean weight is either significantly above or below 50 ounces)
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Question 318886: For the experiment of rolling a pair of dice, what is the probability that the sum of faces is 5?
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Question 318884: A club of 10 members is to select a committee of 3 persons. In how many ways can they do this?
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Question 318883: A club of 10 members is to select 3 officers (president, vice-president, and secretary). In how many ways can they do this?
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Question 318821: Doug wants to find the probability that the average college tuition of his transfer institution will be between $12,000 and $15,500 per year. He knows that the national average is $9800 per year. He collects randomly selected tuition samples from 17 other schools. To calculate this probability, he would best use which distribution?

a) the Student (t) Distribution c) the hypergeometric distribution
b) the Binomial distribution d) the χ2 distribution
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Question 319238: Find the mean, median, sum of squared deviation, variance and standard deviation for the following set of numbers 1112;1245;1361;1372;1472
I come up with
means=1312.4
median=1361
squared=76089.2
variance=15217.84
standard deviation=123.36
Is this correct? if not where did I go wrong?
Click here to see answer by stanbon(57347)

Question 319346: suppose that the time waiting in line has an expected value of 4 minutes, with a standard deviation of 1.2 minutes, and the time it takes to be served by the teller has an expected value of 5.5 minutes, with a standard deviation of 1.5 minutes. Compute the
a. expected value of the total time it takes to be served at the bank
b. standard deviation of the total time it takes to be served at the bank
I think a. is just the total of the expected values. 4+5.5=9.5 but I cannot figure out b.
any help would be appreciated.
Click here to see answer by stanbon(57347)

Question 319333: I'm working a statistic problem and I have gotten up until this point 2.045 over 9 = 0.2272 but how do I get the Standard Deviation. I know it must be something simple but I cannot figure it out the answer was given in class of 4.767 but I don't know how the instructor got it. Help please my email is satin0722@yahoo.com
Click here to see answer by stanbon(57347)

Question 319360: How many unique ways can 10 people fit on a 4-person park bench?
Click here to see answer by Edwin McCravy(8909)

Question 319379: Based on the information given for each of the following studies, decide
whether to reject the null hypothesis. For each, give (a) the Z-score cutoff (or
cutoffs) on the comparison distribution at which the null hypothesis should be
rejected, (b) the Z score on the comparison distribution for the sample score, and(c) your conclusion. Assume that all populations are normally distributed.
Click here to see answer by mrsbph2(1)

Question 319226: 5 step process
Less Tar, more Nicotine? Many cigarette manufacturers market their cigarettes by saying they have low tar. Some people believe that in order to compensate for the low tar and still keep sales high, the manufacturers are increasing the average amount of nicotine in their cigarettes. A group of quality assurance personnel from the FDA sampled 41 low tar cigarettes from brand XYZ. The sample produced an average of 1.5 mg of nicotine with s = 0.33 mg. The national allowable average of nicotine in low tar cigarettes is 1.06 mg. Test the claim that the XYZ brand has a mean amount of nicotine that is greater than the allowable limit. (use a = 0.05)
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Question 319507: A population consists of 15 items, 10 of which are acceptable. In a sample of 4 items, what is the probability that exactly 3 are acceptable? Assume the samples are drawn without replacement
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Question 319515: if two people are each choosing a number between 1 and 900, what is the probability they will choose the same number?
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Question 319529: In a certain town, 10% of people commute to work by bicycle. If a person is selected randomly from the town, what are the odds against selecting someone who commutes by bicycle?

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Question 319482: The mean is u=60 and its stardard devation is q=4.0
Find the probability that X is less that 53
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Question 319572: Can anyone help me with this question? If you have a bag of 8 marbles (5 red and 3 white) and you choose one at random, what are the odds in favor of getting a red marble? Any help would be appreciated! I think the odds are 5/8 (since out of 8 total, 5 are red).

Click here to see answer by Alan3354(30993)

Question 319578: Can anyone help me with this problem? I'm not sure of the best way to arrive at a solution, like a chart or an equation? A pizza parlor offers 3 kinds of salad, 15 kinds of pizza and 4 kinds of desserts. How many different three course meals can be ordered? Can you show me how to solve it? Any help would be appreciated!!
Click here to see answer by user_dude2008(1861)

Question 319651: If posts are spaced 13 feet apart, how many posts are needed for 143 feet of straight-line fence?

Click here to see answer by ankor@dixie-net.com(15652)

Question 319646: What is the probability of obtaining at least one tail when a coin is flipped six times?
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Question 319650: The fire department wants to send booklets on fire hazards to all teachers and homeowners in town. How many booklets does it need, using the following statistics?
35000 homeowners
4000 teachers
1000 teachers who own their own homes

Click here to see answer by checkley77(12569)

Question 319712: An auditor for a government agency is assigned the task of evaluating reimbursement for office visits to physicians paid by Medicare. The audit was conducted on a sample of reimbursements. The sample data are in the ”Sheet 1
(a) Compute a sample mean, a sample standard deviation, and a standard error of the mean.
(b) Is there any evidence that the average reimbursement in the population is exactly $120? Test
this hypothesis at the 1%, 5%, and 10% level of significance, respectively.
Question 2
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Question 319725: You sample 60 of Erika’s neighbors and find that 85% visit regularly. Find the 75% confidence interval for the population proportion of Mac Donnel’s visitors __________________.
n = 60 c = .75
I dont know how to construct a confidence interval for the population proportion?
Click here to see answer by Edwin McCravy(8909)

Question 319777: "Scores on a test are normally distributed with a mean of 61 and a standard deviation of 10.2 Find which separates the bottom 81% from the top 19%"
Click here to see answer by Edwin McCravy(8909)

Question 319778: If an insurance company is hiring for two positions: an actuary and a claims adjuster. How many ways can these positions be filled if there are 9 people applying for the actuary position and 15 people applying for the insurance claims adjuster position?
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Question 319794: What is the formula for finding the test value?
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Question 319754: Find the 24th term of an A.P. whose first term is 24 and common difference is 4.
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Question 319821: The mean diastolic blood pressure for a random sample of 60 people was 89 millimeters of mercury. If the standard deviation of individual blood pressure readings is known to be 8 millimeters of mercury, find a 90% confidence interval for the true mean diastolic blood pressure of all people. Then complete the table below:
What is the lower limit of the 90% confidence interval?
What is the upper limit of the 90% confidence interval?
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Question 319852: I have several questions to this nature...I need an easy explanation as to how these are figured. This one has an answer of "C".
Assume that in a hypothesis test with null hypothesis μ 0 H : = 16.0 at α = 0.10, that a value of 14.0 for the sample mean results in the null hypothesis being accepted. That corresponds to a confidence interval result of
A) There is insufficient information to conclude whether the 95% confidence interval
for the mean contains or does not contain the value 16.0
B) The 95% confidence interval for the mean contains the value 14.0
C) The 95% confidence interval for the mean contains the value 16.0
D) The 95% confidence interval for the mean does not contain the value 16.0
Click here to see answer by stanbon(57347)

Question 319953: A hat contains 32 names, 21 of which are female. If four names are randomly drawn from the hat, what is the probability that at least one male name is drawn?
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Question 319989: A die with 8 sides is rolled. What is the probability of rolling a number less than 5?
Click here to see answer by Edwin McCravy(8909)

Question 320102: Indicate whether the given statement could apply to a data set consisting of 1,000 values that are all different.
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Question 320058: One bag contains 4 red marbles, a second bag contains 2 blue marbles, and a third bag contains 5white marbles. How many total possible ways when 1 marble from each bag be picked?
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Question 320005: Find the point estimate of the population proportion if 85 out of 205 people like chocolate.
I'm not sure if I'm going in the right direction?
85/205 = 0.415
1 - 0.415 = 0.585
Click here to see answer by stanbon(57347)

Question 320012: average yearly cost $186.60
randomly select 30
probability sample mean for the 30 is less than $187.00?
assume s.d. is $27.00
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Question 319933: Forecasters' interest rate predictions over the period 1982-1990 were studied to see whether the predictions corresponded to what actually happened. The 2x2 contingency table below show the frequencies of actual and predicted interest rate movements. At a = .10, is the actual change independent of the predicted change? (Date are from R.A. Kolb and H. O. Steckler, "Howe Well Do Analysis Forecast Interest Rates?" Journal of Forecasting 15, no. 15 (1990), pp. 385-394).
Forecasted Change Rate Fell Rates Rose Row Total
Rates would fall 7 12 19
Rates would rise 9 6 15
Col. Total 16 18 34
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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, 21196..21240