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Question 361603: What is the probability that at least 2 people share the same birthday among 25, 50, 75, 100, 500, and 1000 people. I have tried to run a probability simulation in Excel to generate random numbers (this is required) but my results are supposedly incorrect. For 25 people, my probability was 0.04, for 50 people my probability was 0.06, for 75 people my probability was 0.1467, for 100 people my probability was 0.15, for 500 people my probability was 0.264, and for 1000 people my probability was 0.276. My instructor is saying "consider the number of possible birthdays and the number of people being used. In some situations the probability would be 1 or 100%". I don't understand this at all. The computer generates random numbers, so I don't control which numbers (1-365) are picked. Are my answers correct or am I missing something? Thanks so much!!!
Click here to see answer by stanbon(57347)

Question 361602: Frank Schmuck works for a beverage distribution company. From experience, he understands there is a 15 percent chance he will receive a slight shock whenever he does maintenance on a beverage dispensing machine. Frank is scheduled to work on 8 machines today.
a. What is the probability he will receive a shock on just the first and last machines he works on? ____
b. What is the probability he will not receive a shock from any of the machines? ____
c. Frank just finished working on the 7th machine and he has not yet received a shock. What is the probability he will be shocked on the 8th machine? ____

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Question 361601: The top salesperson of Floor coverings of Tampa insists she has a 65 percent chance of selling a floor covering to any customer she talks to during a normal workday. If She talks to 15 customers today
a. What is the probability she will sell exactly 7 floors? ____
b. What is the probability she will sell more than 10 floors? _____
c. What is the probability she will sell less than 9 floors?
Click here to see answer by stanbon(57347)

Question 361678: which value is the largest? 11/5, 2.05, 2.5, 9/4
Click here to see answer by rfer(12657)

Question 361678: which value is the largest? 11/5, 2.05, 2.5, 9/4
Click here to see answer by mananth(12270)

Question 361735: if two fair dice are rolled, find the probability of a sum of 5 given that the sum is less than 8.
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Question 361726: How many counting numbers in the set (1,2,3,4,......49) are divisible by 2 or 5. Don't count numbers twice.
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Question 361722: p(not5)
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Question 361789: Shavaonna is buying tulip bulbs to plant in her garden. In the catalog she sees a disclaimer that there is a 1/15 probability that a bulb will not flower.
If shavonna orders 90 bulbs, how many tulips wcan she expect to see in her garden?
Click here to see answer by fractalier(2101)

Question 361808: Hello Can someone please help me with this.
Mr. Doodle’s grade distribution over the past 3 years for a course in college algebra is shown in the chart below.
Grade Number
A 45
B 180
C 210
D 95
F 65
I 5
Jane plans to take a college algebra course with Mr. Doodle, determine the empirical probability that she receives an F.
I not sure how to do this but I came up with 1/212 is that right?
Thank you
Click here to see answer by solver91311(16885)

Question 361746: Ana will wear red to class is 20%, and the probability that Jeff will wear red to class is 30%.
what is the probability that they will both wear red in same day to class?
what is the probability that one of them will wear red to class?
X = 2,3,5,1, and Y= 2,2,4,3
∑X2+∑(Y-1)=
Click here to see answer by robertb(4012)

Question 361828: A music equipment outlet stocks ten different guitars, four guitar cases, six amplifiers, and three effects-processors. Assume that all of the items are mutually compatible and suitable. How many different complete setups could a person choose to begin a musical career?
10 * 4 * 6 * 3= 720
Click here to see answer by robertb(4012)

Question 361832: Hello, Can someone help me with this, I am sorry I been out of school for 15 years, and I lost, I don't know where to start.
In a multiple-choice test, each question has five options. Students will get 2 points for each correct answer; lose 1 point for each incorrect answer; and receive no points for unanswered questions. A student does not know the correct answer for one question. Is it to her advantage or disadvantage to guess an answer? Show your calculations for expected value
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Question 361827: A set of three digits is provided {3, 4, 5}. How many five-digit numbers can be formed that begin and end with “3” if unlimited repetitions are allowed?
5 nPr 3= 60

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Question 361825: A committee of four congressmen will be selected from a group of seven democrats and three republicans. Find the number of ways of getting exactly 4 democrats.
10 nCr 4 = 210
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Question 361823: A professor teaches a class of 60 students and another class of 40 students. Five percent of the students in each class are to receive a grade of “A”. In how many different ways can he distribute the “A” grades?
60 nCr 3= 34220
40 nCr 2= 780
34220+ 780= 35,000

Click here to see answer by edjones(7569)

Question 361820: Formulas: nCr = n! / r!(n-r)! Order not Imp.....

nPr = n! / (n-r)! Order is Imp....

Problem 1 (2 Points)

You are at a mountain resort and wish to dine at three different restaurants. A total of 8 restaurants are available, but only two of the eight serve sea food. However, you as a diner do not know that only two restaurants serve sea food. Find the number of ways in which you can select a restaurant for dining so that at least one of the selected restaurants will serve seafood. Assume that the order of selection is not important.
at least 1= 1 or more = 1 0r 2 or 3 or 4 or 5 or 6 or 7 or 8 = 8C1+8C2+ 8C3 +8C4+8C5+8C7+8C8= 255
Click here to see answer by edjones(7569)

Question 361728: How many subsets of 3 elements does the set (a, b, c, d, e, f) have?
Click here to see answer by robertb(4012)

Question 361744: All of the following are characteristics that define a binomial random variable except
a. the outcome of one trial depends on the outcome of the previous trial.
b. outcomes are classified as either a success or a failure.
c. there are a fixed number of trials of an experiment.
d. the probability of a success is the same for each trial.

Click here to see answer by edjones(7569)

Question 361724: Billy has 5 coins, 1 penny, 1 nickel, 1 dime, 1 quarter, and 1 half-dollar. How many different sums of money can Billy form by using 1, 2, or 3 of these coins?
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Question 361921: You are conducting a two-tailed test of means but your software package only calculates a one-tailed p-value equal to 0.13. The actual p-value for your test is
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Question 361959: there are 11 black marbels 34 red marbels and 12 green marbels in the jar of life. if you are blind folded and allowed to choose a marble,the probabilty of choosing a black marble is
Click here to see answer by ewatrrr(10682)

Question 361978: Hello, Can someone please help me with this problem, I am confused. I really need your help. Thank you
One thousand raffle tickets are sold for $1.00 each. One grand prize of $200 and two consolation prizes of $50 each will be awarded. Jeremy purchases one ticket. Find his expected value. Show your work for full credit.
Click here to see answer by ewatrrr(10682)

Question 361980: Hello, Can you please help me.
A person spins the pointer and is awarded the amount indicated by the pointer. Circle with left half $2.00 the upper right quarter is $12 and the lower right quarter is $5.00 and it cost $6 to play the game. I can not post the picture.
• The expectation of a person who plays the game.

• The fair price to play the game.

Show your work for full credit.
Thank you,
Confused

Click here to see answer by ewatrrr(10682)

Question 361981: Hello, Can you please help me.
One thousand raffle tickets are sold for $1.00 each. One grand prize of $200 and two consolation prizes of $50 each will be awarded. Jeremy purchases one ticket. Find his expected value. Show your work for full credit.
Thank you,
Confused
Click here to see answer by ewatrrr(10682)

Question 361985: In a class of 28, 4 out of 16 girls and 7 out of 12 boys wear contact lenses. A student is chosen randomly from the class.
(a) What is the probability that the chosen student is not wearing contact lenses?
(b) What is the probability that the chosen student is a girl or someone who does not wear contact lenses?
(c) If the chosen student is wearing contact lenses, what is the probability that the chosen student is a boy?
(d) If G represents the event that the chosen student is a girl and C represents the event that the chosen student wears contact lenses, determine whether events G and C are independent.

Click here to see answer by edjones(7569)

Question 361958: If two events A and B are independent and you know that P(A) = 0.45, what is the value of P(A | B)?
P(A|B) =
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Question 361911: a sample poll of 1000 voters reveal the following information about candidate A, B and C who are nominated for three different offices. 200 are in favor of candidate A, 500 are in favor of candidate B, 500 are in favor of candidate C, 100 in favor of both A and B,100 in favor of both A and C, 250 in favor of both candidate B and C, 100 in favor of all three candidates.
Donate by A, B and C the event that the selected product favors candidates A, B and C respectively.
Required: Are the three events statistically independent, explain.
Click here to see answer by edjones(7569)

Question 362037: in one town, 56% of all voters are Democrats. If two voters are randomly selected for a survey, find the probability that they are both Democrats.
Click here to see answer by Fombitz(13828)

Question 362042: A student is taking a multiple choice exam with 16 questions. Each question has five alternatives. If the student guesses on 12 of the questions what is the probability she will guess at least 8 correct?
Click here to see answer by edjones(7569)

Question 362036: 2.100 ) The probability that a one-car accident is due to faulty brakes is 0.04 , the probability that a one-car accident is correctly attributed to faulty brakes is 0.82 , and the probability that a one-car accident is incorrectly attributed to faulty brakes is 0.03 . What is the probability that :
a) A one-car accident will be attributed to faulty brakes;
b) A one-car accident attributed to faulty brakes was actually due to faulty brakes .

Click here to see answer by edjones(7569)

Question 361717: Two cards are drawn in succession, without replacement, from a standard deck of 52 cards. In how many ways could these be a black jack and a red card in that order?
There are two black jacks in a deck. If you draw one then there are now 51 cards left. There are 26 red cards in a deck so the probability of drawing red is 26/51. I don't know where to go from here...
Click here to see answer by scott8148(6628)

Question 361892: Suppose two cards are drawn from a standard deck of cards. Find the probability that the
second card is a prime number given that the first card is not a prime number.

Click here to see answer by Fombitz(13828)

Question 362220: If a company is randomly selected from the list of 20 studied, what is the probability:
Click here to see answer by Alan3354(30993)

Question 362271: Suppose that 85% of all federal tax returns filed last year are free of arithmetic errors. A random sample of seven returns is to be drawn. What is the probability of five returns being error free?
Click here to see answer by robertb(4012)

Question 362150: I need help .. ?
The numbers 1,2,3, and 4 are written on separate slips of paper and placed in a hat. Two slips of paper are then randomly, one after the other and without replacement.
a) Make a tree diagram showing the 12 possible outcomes of this experiment.
b) Find the probability that the sum of the numbers picked is 6 or more.
Explain it as well..
Thanks
Click here to see answer by stanbon(57347)

Question 362276: 41) The food marketing institute shows that 17% of households spend more than $100 per wee on groceries. Assume the population proportion is p=.17 and a simple random sample of 800 households will be selected from the population.
a) Show the sampling distribution of p, the sample proportion of households spending more than $100 per week on groceries.
b) What is the probability that the sample proportion will be with in plus or minus .02 of the population proportion?
c) Answer part (b) for a sample of 1600.
Click here to see answer by stanbon(57347)

Question 362103: In the United States, the National Health Survey has determined that women’s weights are normally distributed with a mean of pounds and a standard deviation of pounds.
1. If 1 woman is randomly selected, find the probability that her weight is between 140 and 150 pounds.

Click here to see answer by stanbon(57347)

Question 362306: Elected Board of Directors. There are 12 members on the board of director for the Newport General Hospital. (a) If they must elect a chairperson, first vice chairperson, second vice chairperson and secretary, how many different slates of candidates are possible? (b) If they must form an ethics subcommittee of four members, how many different subcommittees are possible?
Click here to see answer by edjones(7569)

Question 362397: At your university 30% of the undergraduates are from out of state. If you randomly select 8 of the undergraduates, what is the probability that all are from within the state?
Click here to see answer by robertb(4012)

Question 362454: The mean of 7 positive integers is 405. Two of the integers are 103 and 199 and
the other numbers are greater than 199. If all 7 integers are different, what is
the greatest possible value for any of the 7 integers?
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Question 362466: find the n needed to obtain a p-hat between (p-0.01, p+0.01) with 95% probability
Click here to see answer by stanbon(57347)

Question 362457: 1).a set of 50 data values has a mean of 40 and a variance of 25.
a). Find the standard score (z) for a data value = 47.
b). Find the probability of a data value >47.

(2). Find the area under the standard normal curve:
I. to the right of z = 1.83
II. to the left of z = 1.83

Click here to see answer by stanbon(57347)

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