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Question 349758: A group of three seniors, six juniors, and five sophomores must select a committee of three. How many committes are possible of the committtee must contain the following
Click here to see answer by Alan3354(31518)

Question 349869: If you have 5 blood samples combined in one mixture and the mixture will only test negative if all the individual samples are negative, What is the probability the mixture will test positive, if the probability of an individual positive sample is 0.09?
Click here to see answer by edjones(7569)

Question 350098: If the odds in favor of your winning a bet are 3 to 8, what are the odds against winning the bet?
Click here to see answer by Fombitz(13828)

Question 350096: If a fair die is tossed one time, find the probability of getting a number less than 3 or an odd number.
thank-you
Click here to see answer by Fombitz(13828)

Question 350100: A restaurant offers make it yourself entrees. You can choose from five meats, eight vegetables, and three breads. Assuming that you must choose exactly one item from each group, how many different dinners can be ordered?
Thanks!
Click here to see answer by stanbon(57966)

Question 350097: Two students from a class of 40 are to be selected to represent the class at a student council meeting. In how many ways can the two students be selected?
Click here to see answer by stanbon(57966)

Question 350110: If the probability of a student graduating from college with a 4.0 GPA is 0.008, what is the probability of a student graduating from college with less than a 4.0 GPA?
Click here to see answer by Fombitz(13828)

Question 350116: A bag contains 4 blue marbles, 3 red marbles, 2 green marbles and a white marble. You reach in and randomly pick one marble, set it aside, and then randomly pick a second marble. What is the probability of picking two blue marbles?
Click here to see answer by Fombitz(13828)

Question 350109: Suppose you own 30 cassette tapes and 20 CDs. If you wish to select 5 tapes and 3 CDs to take on a trip with you, in how many ways can you make your selection?
Click here to see answer by stanbon(57966)

Question 350121: A bag contains 4 blue marbles, 3 red marbles, 2 green marbles and 1 white marble. You reach in and randomly pick one marble, set it aside, and then randomly pick a second marble. What is the probability of picking a red marble and then a green marble?
Click here to see answer by stanbon(57966)

Question 350119: A jar of marbles contains a total of 14 marbles, 4 are red, 4 are blue, 4 are green and 2 are white. Suppose you draw a marble, replace it, then draw a second marble. Find the following probabilities. Write anser in fractoin form.
1. red, then blue
2. blue, then white
3. neither are green
4. both are blue
also, teacher wants to know if this is a dependent or independent event?
I really need the process on which to solve these...so if you could just let me know that and the answer to one of these.
Thanks very much!!
Click here to see answer by edjones(7569)

Question 350023: A fast food chain store conducted a taste survey before marketing a new hamburger. The results of the survey showed that 70% of the people who tried it liked the hamburger. Assume that 70% of all people like this hamburger. On a certain day, 8 customers bought it for the first time.
(b). Find the probability that at least 5 people like the hamburger.
(c). Find the probability that at most 4 people like the hamburger.
(d). What is the expected number of people who will like the hamburger ?
(e). Find the standard deviation of the number of people who like the hamburger.
Click here to see answer by edjones(7569)

Question 350137: a test consist of 10 true and false questions. To pass the test a student must answer at least eight questions correctly. If a student guess on each question, what is the probability that the student will pass the test?
Click here to see answer by edjones(7569)

Question 350161: Twenty mp3 players are produced in a production run. The probability of producing a defective mp3 player is 3%. What is the expected number of NON-defective mp3 players in the production run? What is the probability that at least 17 mp3 players are NON-defective?
Click here to see answer by edjones(7569)

Question 350181: Only 4% of people have Type AB
blood. A bloodmobile has 12 vials of blood on a rack. If the dis-
tribution of blood types at this location is consistent with the
general population, what’s the probability they find AB blood in:

a) None of the 12 samples?
b) At least 2 samples?
c) 3 or 4 samples?
Click here to see answer by edjones(7569)

Question 350178: Xˆз=7
Click here to see answer by Fombitz(13828)

Question 350153: The unemployment rate in a city is 13%. Find the probability that at least 3 out of 8 people from this city sampled at random are unemployed. Round your answer to four decimal places.
Click here to see answer by Fombitz(13828)

Question 349782: Let X be a random variable with pdf f(x) = kx^2 where 0 is less than or equal to x which is less than or equal to 1.
(a) Find k.
(b) Find E(X) and Var(X).
Click here to see answer by Fombitz(13828)

Question 350252: What is the difference between a point estimate and a confidence interval estimate? Does the confidence interval always contain the true population parameter? Yes or No. I think it is yes.
Interpret what is meant by a 95% confidence interval.
Click here to see answer by stanbon(57966)

Question 350176: Us e the compound interest formula A=P(1+r)t and the given information to solve for. A=$9,000,000 P=$20,000 t=40

Click here to see answer by stanbon(57966)

Question 350275: Statistic: Counting and Multiplication Principle
here is my problem!
1) seven shoppers arrive simultaneously at the express lane checkstand of a local supermarket. If the shoppers line up at random, what's the probability they end up in the alphabetical order of their names?
2)Suppose 6 notes were written and 6 envelopes were addressed. Accidentally, the notes were inserted into the envelopes at random and then mailed. What is the probability all the notes arrive at the correct destination?
3) Four people get on a bus that makes six regular stops. Find the probability that at least two of the people get off the bus at the same stop?
Click here to see answer by edjones(7569)

Question 350367: Xˆз=11 (round to four decimal places as needed.)
Click here to see answer by solver91311(17077)

Question 350364: Roy’s property tax is $634.69 and is due April 5. He does not pay until July 30. The county adds a penalty of 7.9% simple interest on unpaid tax. Find the penalty using exact interest. (round to the nearest cent.)
Click here to see answer by checkley77(12569)

Question 350382: what is a good math problem for a sales
clerk
Click here to see answer by jim_thompson5910(28715)

Question 350359: I need someone to fully explain how to get this answer ns easy terms. Please include step by step instructions to figure this out. I am struggling with this class and have other questions to answer. Thank you for your help!
A clinical trial is conducted to compare an experimental medication to placebo to reduce the symptoms of asthma. Two hundred participants enrolled in the study and randomized to receive either the experimental medication or placebo. The primary outcome is a self-reported reduction of symptoms. Among 100 participants who received the experimental medication, 38 reported a reduction of symptoms as compared to 21 participants of 100 assigned to the placebo.
a. Generate a 95% CI for the difference in proportions of participants reporting a reduction of symptoms between the experimental and the placebo groups?
b. Estimate the RR for reduction in symptoms between groups?
c. Estimate the OR for reduction in symptoms between groups?
d. Generate a 95% CI for the RR?
Click here to see answer by stanbon(57966)

Question 350015: A bakery shop sells loaves of fresh French bread. Any unsold loaves at the end of the day are either discarded or sold elsewhere at a loss. The demand for this bread has followed a normal distribution with a mean = 35 loaves and variance/sigma = 8 loaves.
a) If 40 loaves are to be made each day, what is the probability of not meeting demand?
b) How many loaves should the bakery make each day so that they can meet the demand 90% of the time?
c) What is the probability of exceeding 38 loaves, given that the demand exceeds 35?

Click here to see answer by stanbon(57966)

Question 350592: In an article in the Journal of Management, Joseph Martocchio studied and estimated the costs of employee absences. Based on a sample of 176 blue‐collar workers, Martocchio estimated that the mean amount of paid time lost during a three‐month period was 1.4 days per employee with a standard deviation of 1.3 days. Martocchio also estimated that the mean amount of unpaid time lost during a three‐month period was 1.0 day per employee with a standard deviation of 1.8 days. Suppose we randomly select a sample of 100 blue‐collar workers. Based on Martocchio's estimates, find:
a. What is the probability that the average amount of paid time lost during a three‐month period for the 100 blue‐collar workers will exceed 1.5 days?
b. What is the probability that the average amount of unpaid time lost during a threemonth period for the I00 blue‐collar workers will exceed 1.5 days?
c. For the amount of paid time lost, the probability is 60% that the sample mean will be between what two values, symmetrically distributed around the population mean?
Click here to see answer by stanbon(57966)

Question 350543: Is the mean height for all adult American males between the ages of 18 and 21 now over 6 feet? If the population of all adult American males between the ages of 18 and 21 has mean height of μ feet and standard deviation σ feet, to answer this question one would test which of the following null and alternative hypotheses?

Click here to see answer by stanbon(57966)

Question 350602: When the car park at Brinsons empties at the end of the day, the probability that a car turns left at the first junction is 3/4 and that a car turns left at its NEXT junction is 2/5. A car leaves the car park. What is the probability that
a) It turns right and then right again
b) It makes one left turn and one right turn at the first two junctions it encounters.
Click here to see answer by stanbon(57966)

Question 350618: For a certain candy, 10% of the pieces are yellow, 15% are red, 20% are blue, 15% are green, and the rest are brown.
If you pick three pieces in a row, what is the probability that at least one of them is green?
Click here to see answer by ewatrrr(10682)

Question 350625: average=1000
standard deviation=300
randomly selected=50
what is the probability that the mean is greater than 1100

Click here to see answer by Fombitz(13828)

Question 350626: average=1000
standard deviation=300
randomly selected=50
what is the probability that the mean is greater than 1100

Click here to see answer by Fombitz(13828)

Question 350678: Let z denote a variable that has a standard normal distribution. Determine the value z* to satisfy the conditions below. (Round all answers to two decimal places.) P(z > z* or z < -z*) = 0.1974
z* = ?
Click here to see answer by Fombitz(13828)

Question 350681: Determine the value of z* such that satisfies the conditions below. (Round all answers to two decimal places.) -z* and z* separate the middle 95% of all z values from the most extreme 5%
z* =?
Click here to see answer by Fombitz(13828)

Question 350677: Why isn't spinning a roulette wheel 4 times, keeping track of the winning
>numbers a binomial of distribution?
>
> A test consists of 10 true/false questions. To pass the test a student must
> answer at least 7 questions correctly. If a student guesses on each
> question, what is the probability that the student will pass the test?
>
> A study conducted at a certain college shows that 75% of the school's
> graduates find a job in their chosen field within a year after graduation.
> Find the probability that 8 randomly selected graduates all find jobs in
> their chosen field within a year of graduating.
>
> You are dealt two cards successively (w/o replacement) from a shuffled deck
> of 52 playing cards. Find the probability that both cards are black.
>
> Find the standard deviation if x=0 and P(X)=.15, x=1 and P(X)=.33, x=2 and
> P(x)=.05, x=3 and P(x)=.19, x=4 and P(x)=.28
>
> Thank you and if you could show me how you worked the problems out that
> would be very helpful!
>
Click here to see answer by Fombitz(13828)

Question 350694: A test consists of 10 true/false questions. To pass the test a student must
> answer at least 7 questions correctly. If a student guesses on each
> question, what is the probability that the student will pass the test?
Click here to see answer by jjordan95(63)

Question 350708: A study conducted at a certain college shows that 75% of the school's graduates find a job in their chosen field within a year after graduation. Find the probability that 8 randomly selected graduates all found jobs in their chosen field within a year of graduating.
Thanks for the help, my original answer was 6, but it was wrong.
Click here to see answer by ewatrrr(10682)

Question 350693: A study conducted at a certain college shows that 75% of the school's
> graduates find a job in their chosen field within a year after graduation.
> Find the probability that 8 randomly selected graduates all find jobs in
> their chosen field within a year of graduating.
Click here to see answer by ewatrrr(10682)

Question 350733: Seven prizes are to be given to seven different people in a group of thirteen. In how many ways can a first prize, a second prize, a third prize and four fourth prizes be given?

Click here to see answer by jim_thompson5910(28715)

Question 350747: At the Glenridge quarry park ( a great place to check out if you have not been there yet), there are bullfrogs as big as a bread and butter plate. On a warm day they sit on the bank and jump into the water if they hear you coming. A maximum of 3 bullfrogs can sit on one particular sloped area. The following shows a probability distribution of seeing x frogs there during a lunch time walk.
x 0 1 2 3
P(x) 0.2 0.62 0.13 0.05
Consider a random lunch time walk.
A. Find the probability that 1 or fewer are seen.
B. Find the expected number of bullfrogs.
C. Find the standard deviation of the number of bullfrogs.

Click here to see answer by Fombitz(13828)

Question 350742: This past summer the LifeSaving Society did a survey about who was at risk in the water, with the goal of reducing swimming accidents. (Globe and Mail July 15 2010)
Consider a similar study done that shows that 96 % of those born in Canada can swim but only 83 % of new Canadians can swim. In a random group of 12 new Canadians, find the probability that exactly 8 can swim.
Click here to see answer by stanbon(57966)

Question 350687: HELP!!! I am completely lost in statistics!! Any assistance is greatly appreciated!
I need help with the following questions:
A survey of randomly chosen new students at a certain university revealed the data below
concerning the main reason for choosing this university instead of another. Research question: At α = .01, is the main reason for choosing the university independent of student type? Students
New Student Tuition Location Reputation Row Total
Freshmen 50 30 35 115
Transfers 15 29 20 64
MBAs 5 20 60 85
Col Total 70 79 115 264
and
Final exam scores for a sample of 20 students in a managerial accounting class are shown. (a) At α = .05, is there a difference in the population median scores on the two exams? Make an Excel worksheet for yourWilcoxon signed-rank test calculations and check your work by using MegaStat or a similar computer package. (b) Perform a two-tailed parametric t test for paired two-sample means by using Excel or MegaStat. Do you get the same decision? Accounting
Student Exam 1 Exam 2 Student Exam 1 Exam 2
1 70 81 11 84 96
2 74 89 12 95 96
3 65 59 13 83 99
4 60 68 14 81 76
5 63 75 15 59 68
6 58 77 16 54 47
7 72 82 17 75 84
8 71 69 18 92 100
9 52 53 19 70 81
10 79 84 20 54 58

Click here to see answer by stanbon(57966)

Question 350950: The NY Dept of Motor Vehicles (DMV) designs its license plates with space for 7 letters or numerals. In the most recent iteration, the DMV uses 3 letters followed by 4 numbers. Since the first 3 spaces are always letters, assume that I and O are valid possibilities. How many different license plate numbers are possible?
Click here to see answer by stanbon(57966)

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, 21241..21285, 21286..21330, 21331..21375, 21376..21420, 21421..21465, 21466..21510, 21511..21555