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Question 559339: students recieve 1 of 4 versons of a math test (a,b,c,d). whats the probability that at least 3 of the 5 students tested will get version A?
Click here to see answer by stanbon(57290)

Question 559132: About 20% of the population is hopeless romantic.What is the probability that at least one is hopelessly romantic?
Click here to see answer by richard1234(5390)

Question 558903: player 1 chooses a number between 1 and 10. Then player 2 chooses a number between 1 and 10. What is the probability of player 2 choosing a higher number than player 1?
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Question 559432: I am trying to figure this out.
What is the probability that in 1800, when the Earth's population was around 900 million people, that one person would see a need (people starving in Ireland) and take action, but that action created hospitals, schools and other needs for people who could not afford it.
Then taking into account that they were from Ireland, impacted by wars to come, famine, disease, and persecution and that now they have several successful hospitals world wide.
I realize that I could divide 1/900,000,0000, but that wont answer my question really. When you figure in the 6 degrees of separation to this - it really becomes a mind boggling and I'd really like to figure this out because I have some other probabilty questions to piggy back on this.
1 - that the one persons actions would affect someone directly in the year 1942, in Phoenix Arizona, at St. Josephs Hospital. -
2. Once that answer is known - then the fact that the someone is from Kansas, took a drive to Phoenix and met someone at the hospital.
Thank you for your help.
Michael
Click here to see answer by richard1234(5390)

Question 559472: This probability distribution shown below relates to the number of times a person goes to a local coffee shop per day. What is the expected mean (average) number of times a person goes to a local coffee shop per day?
x p(x)
0, 0.65
1, 0.15
2, 0.2
please solve and show me how you solved it.
Click here to see answer by stanbon(57290)

Question 559471: If the probability of defective bolt be 1/10,Find the mean and variance for binomial distribution of defective bolts in a sample of 400 bolts.
Click here to see answer by AnlytcPhil(1276)

Question 559481: 1500 people polled whether they liked strawberry, chocolate or vanilla ice cream.
250 liked strawberry
700 liked chocolate
520 liked vanilla
30 liked other flavors
What is the probability that the next person will say their favorite is chocolate?
Click here to see answer by AnlytcPhil(1276)

Question 559724: two numbers were rolled 100 times.
A sum of less than 5 appeared 18 times.
Click here to see answer by Alan3354(30993)

Question 559724: two numbers were rolled 100 times.
A sum of less than 5 appeared 18 times.
Click here to see answer by solver91311(16877)

Question 559487: A slot machine has three reels, each reel has 15 symbols. What are the odds of two of the same symbols hitting on a spin? and What are the odds of all three symbols matching on a spin?
Click here to see answer by richard1234(5390)

Question 560128: If 2% of all calculators are defective, find the mean, variance, and standard deviation of a lot of 400 calculators.
Click here to see answer by stanbon(57290)

Question 560091: What is the slope of the line given by the equation below? If necessary, use the slash mark ( / ) for a fraction bar.
y=6/5 x
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Question 560064: About 20% of the population is hopeless romantic.There are 2 that are being surveyed.What is the probability that at least one is hopelessly romantic?
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Question 560130: Suppose that 10% of Americans are afraid of being alone in a house at night. If a random sample of 13 Americans is selected, find the following probability by using a binomial table. Give your final answer to to three decimal places. There are exactly 4 people in the sample who are afraid of being alone at night.
Click here to see answer by stanbon(57290)

Question 560134: Assume the following variables are binomial.(Note: If values are not in a binomial distribution table, use the binomial formula. Round answer to 3 decimal places.)
Find the probability that at least 6 had CD player for a sample of 12 teenagers if 70% of them had compact disk players by the age of 16.
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Question 560062: A lottery has 52 numbers. In how many different ways can 6 of the numbers be selected? Order of selection is no important.
Click here to see answer by stanbon(57290)

Question 560014: an internet e-business server receives between 0 and 2950 Http requests per hour. these requests are uniformly distributed.
what is the probability of receiving between 500 and 600 requests per hour?
Click here to see answer by stanbon(57290)

Question 560152: in a scientific study there are 12 guinea pigs, 5 of which are pregnant. If 3 are selected at random without replacement, find the probability that none are pregnant
Click here to see answer by nyc_function(2733)

Question 560139: check the data for outliers
4, 6, 12, 14, 18, 24, 30, 60
A. No outliers exist
B.The value 6 can be considered an outlier
C.The value 60 can be considered an outlier
D.The value 24 can be considered an outlier
Click here to see answer by Edwin McCravy(8901)

Question 560189: A positive integer is picked randomly from 51 to 60, inclusive.
what is the probability that it is divisible by both 2 and 3?
Click here to see answer by stanbon(57290)

Question 560171: Smith Widget Company makes widgets for the medical industry. One particular customer requires widgets that meet FDA standards. One FDA standard requires Z-testing of at least 100 widgets at a time at the .01 level of significance. The specific standard requires that widgets be no smaller than a certain tolerance and no larger than a certain tolerance. The critical value(s) for such a test would be: __________
Click here to see answer by stanbon(57290)

Question 560162: Assume that the sample is taken from a large population and the correction factor can be ignored.
The average public elementary school has 450 students. Assume the standard deviation of the distribution is 98. If a random sample of 35 public elementary students is selected, find the probability that the number of students enrolled is between 447 and 456. Give answer as a percent rounded to two decimal places.
Click here to see answer by stanbon(57290)

Question 560157: A medical researcher wishes to determine the percentage of females who take vitamins. He wishes to be 99% confident that the estimate is within 2% of the true proportion. How large should the sample size be?
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Question 560154: Suppose that 10% of Americans are afraid of being alone in a house at night. If a random sample of 12 Americans is selected, find the following probability by using the binomial table. There are exactly 3 people in the sample who are afraid of being alone at night.
Click here to see answer by stanbon(57290)

Question 560226: a single fair die is tossed. find the probability of obtaining a number different than 7
Click here to see answer by rapaljer(4667)

Question 560228: stanwood builders has a development of new homes. there are three different floor plans, four exterior colors, and an option of either a two car or three car garage. how many are there for one home?
Click here to see answer by stanbon(57290)

Question 560156: A researcher wishes to estimate, with 95% confidence, the proportion of people who own a home computer. A previous study shows that 36% of those interviewed had a computer at home. The researcher wishes to be accurate within 2% of the true proportion. Find the minimum sample size necessary.
Click here to see answer by stanbon(57290)

Question 560023: Pick a block of three digits from a random digit table. What is the probability that the block picked is less than 600?
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Question 560293: an investor owns 3 common stocks. each stock, independent of the others, has equally likely chances of 1. increasing in value, 2. decreasing in value, or 3. remaining the same value. list the possible outcomes of this experiment. estimate at least two of the stocks increase in value.
Click here to see answer by stanbon(57290)

Question 560244: Are these answers correct ?
All groups do question # 1, their group question, and prepare to respond to one other question. For each question determine if the situation is a permutation or combination and if it is with or without replacement, then determine the answer.
Identify each of the following 1) as a permutation or combination and 2) as with or without replacement:
Social security numbers permutation and without replacement
Books in your backpack Combination and without replacement
Numbers chosen for the “Big” lotto Combination and with replacement
The cards in your hand for a card game Combination and without replacement
Lunch chosen by a student from the cafeteria menu Combination and with replacement.

5 A cafeteria offers 4 main menu selections, 5 salad selections, 3 fruit selections and 8 drink selections. How many ways can a student choose a lunch if
The student chooses one of each of the selections?
4*5*3*8=480 selections
The student chooses two different main menu selections (must be different) and one salad?
30
In calculator select 4, nCr, 2=6; same with 5C_r =5 5*6=30
The student chooses 3 salads (different), and a fruit?
=30
The student chooses 4 salads (must be different), and a fruit?
=15
The student chooses 5 items (main, salad or fruit), all different, and a drink?
6336
The student chooses 2 different main menu items, 2 different salads, 2 pieces of different fruits and 1 drink (he plays football and is hungry!)
1440
Which of these are combinations and which are permutations? Which are with and which without replacement?
All of them are combination and without replacement.

Click here to see answer by KMST(1868)

Question 560314: Please help me solve this problem. Measures of central tendency. After four algebra tests, Alisa has a mean score of 82. One more 100-point test is to be given in the class. All the test scores are equal importance. Is it possible for Alisa to raise her average(mean) to 90? Please explain. Thank you.
Click here to see answer by Theo(3458)

Question 560313: a supplier of components to an industry makes a product which sometimes fails immediately it is used. He control his manufacturing process so that the proportion of faulty products is supposed to be only 5%. Out of 400 supplies in a batch 26 prove to be faulty. Verify the manufacturer's claim. Use 0.05 level of significance
Click here to see answer by Theo(3458)

Question 560311: Please help me work this problem using percentiles. Rene scored at the 84th percentile on a test given to 12,600 students. How many students scored higher than Rene?
Click here to see answer by stanbon(57290)

Question 560309: There are four entrances to the Government Center Building in downtown Philadelphia. The building maintenance supervisor would like to know if the entrances are equally utilized. To investigate, 400 people were observed entering the building. The number using each entrance is reported below. At the .01 significance level, is there a difference in the use of the four entrances?
Entrance Frequency
Main Street 140
Broad Street 120
Cherry Street 90
Walnut Street 50
Total 400

Click here to see answer by stanbon(57290)

Question 560360: A population has _ _ 100 and _ _ 20. If you select a single score from this population, on the average, how close would it be to the population mean? Explain your answer.
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Question 560308: In a particular market there are three commercial television stations, each with its own evening news program from 6:00 to 6:30 P.M. According to a report in this morning's local newspaper, a random sample of 150 viewers last night revealed 53 watched the news on WNAE (channel 5), 64 watched on WRRN (channel 11), and 33 on WSPD (channel 13). At the .05 significance level, is there a difference in the proportion of viewers watching the three channels?
Gift Frequency
Sweatshirt 183
Coffee cup 175
Earrings 142

Click here to see answer by stanbon(57290)

Question 560722: calculate the confidence interval for age of 62 adolescent girls,if the mean was 992?
Click here to see answer by stanbon(57290)

Question 560739: Out of 274 listed species of birds in the United States, 78 species made the endangered list. Find the ratio of endangered species of birds go listed species in the united states
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Question 560262: A card is drawn from a standard deck of 52 cards. Find the probability that the card is either a six or a black card.
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Question 560747: When 154 6th graders are asked about how long they sleep each night. what is the probability for the following: 5 will be the answer, 6 will be the answer, 7 will be the answer, 8 will be the answer, 9 will be tge answer and 10 will be the answer?
Click here to see answer by stanbon(57290)

Question 560798: Arthur normally wins 1 out of every 3 backgammon games he plays. In other words, the probability that Arthur wins when he plays backgammon is 1/3. Suppose Arthur plays 4 games. What is the probability that he will win 3 and lose only one?
Click here to see answer by stanbon(57290)

Question 560758: . In a particular suburb, 50% of the households have installed electronic security systems.
a. If a household is chosen at random from this suburb, what is the probability that this household has not installed an electronic security system?
b. If two households are chosen at random from this suburb, what is the probability that neither has installed an electronic security system?

Click here to see answer by stanbon(57290)

Question 560851: 4. Elizabeth had a bad night and didn’t study for her English test. She is so stressed that she can’t remember anything about Oedipus Rex. Her test is 20 multiple choice questions with 5 possible answers each. She has no choice but to guess on each question.
a. How many questions can Elizabeth expect to get correct by guessing?
b. What is the probability that she passes the test? (Her final grade is at least a 70.)
c. What is the probability that Elizabeth answers only 5 questions correctly?
d. What is the probability that she answers less than 10 questions incorrectly?

Click here to see answer by stanbon(57290)

Question 560872: A single fair die is tossed. Find the probability of obtaining a number less than 6.
Click here to see answer by rapaljer(4667)

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