Tutors Answer Your Questions about Probability-and-statistics (FREE)
Question 476296: Suppose we have a set of blood pressures with a mean of 120 Systolic, and a sample standard deviation of 20 points. Assuming a normal distribution of Systolic blood pressures, between what two values should 95% of all Systolic blood pressures lie?
Thanks
Click here to see answer by stanbon(57203)  |
Question 476297: SAT I scores around the nation tend to have a mean scale score around 500, a standard deviation of about 100 points and are approximately normally distributed. A person who scores (a perfect) 800 on the SAT I has approximately what percentile rank within the population?
Thanks
Click here to see answer by Theo(3458)  |
Question 476261: If the argument below is valid, name which of the four valid forms of argument is represented. If it is not valid, name the fallacy that is represented.
If the water is filtered, then it does not contain lead.
The water does not contain lead.
Therefore, the water is filtered.
Click here to see answer by Theo(3458) |
Question 476359: USA today reported that about 47% of the general consumer population in the U.S. is loyal to the automobile manufacturer.of their choice. Suppose Cheverlet did a study of a random sample of 1006 Chevrolet owners and found that 495 said that they would buy another Chevrolet.
a) Should you conclude that the population proportion of consumers loyal to Chevrolet is more than 47%? use the 5% significance level
b)to the nearest whole percent, specify the smallest significance level that would change your decision
Click here to see answer by stanbon(57203) |
Question 476366:
A university admitted 100 students who transferred from other institutions. Of these students, 34 transferred from two-year community colleges, 25 transferred from private four-year institutions, and the rest transferred from public four-year institutions. If two different students are to be selected at random from the 100 students, what is the probability that both students selected will be students who transferred from two-year community colleges?
Click here to see answer by stanbon(57203) |
Question 476509: Local bakery bakes more than a thousand 1-lb loaves of bread daily, and weights of these loaves vary. The mean weight is 1lb 1oz or 482 grams. Assume that the standard deviation of the weights is 18 grams and that a sample of 40 loaves is to be randomly selected.
A. This sample of 40 has a mean value of x, which belongs to a sampling distribution. Find the shape of this sampling distribution.
I don't understand how to find the slope. HELP!
Click here to see answer by robertb(4012)  |
Question 476447: People end up tossing 12% of what they buy at the grocery store (Reader's Digest, March, 2009). Assume this is the true population proportion and that you plan to take a sample survey of 540 grocery shoppers to further investigate their behavior.
a.Show the sampling distribution of (p), the proportion of groceries thrown out by your sample respondents (to 4 decimals)?
b.What is the probability that your survey will provide a sample proportion within ±.03 of the population proportion (to 4 decimals)?
c.What is the probability that your survey will provide a sample proportion within ±.015 of the population proportion (to 4 decimals)?
Click here to see answer by robertb(4012) |
Question 476256: Please can someone help me with this question it is a 2 part question and I don't understand either part please explain in details.
I.Use Chebyshev's theorem to find what percent of the valuses will fall between 156 and 276 for a data set with a mean of 216 and standard deciation of 12.
II. Use the Emperical Rule to find what two values 68% fo the data will fall between for a data set with a mean of 219 and standard deviation of 20. need answered ASAP PLEASE..
Click here to see answer by robertb(4012) |
Question 476505: Karen moved into a new apartment she had four boxes for the kitchen and six boxes for the bedroom. The movers paid no attention to their contents and randomly placed four boxes in the bedroom. Find the probability that three of the boxes were for the bedroom and one for the kitchen.
Click here to see answer by Maths68(1474)  |
Question 476564: classes frequency
0-10 4
10-20 8
20-30 7
30-40 10
In this how to draw a frequency polygon?
since as we know that the class previous of the first will -10-0.....please help me to draw this frequency polygon?
Click here to see answer by Theo(3458) |
Question 476611: I am totally lost, I have almost all the answers here but I need help creating a tree chart. If someone could please look over my work and help point me in the right direction I would appreciat it.
Qustion. New Computer You visit Computer City to purchase a new computer system. You are going to purchase a computer, printer, and monitor from among the following brands.-
Computer
Printer
Monitor
Compaq
Hewlett-Packard
Omega
IBM
Epson
Toshiba
Gateway
Dell
a)Determine the number of points in the sample space.
b)Construct a tree diagram and determine the sample space.Determine the probability of selecting
c)a Gateway computer.
d)a Hewlett-Packard printer.
e)a Gateway computer and a Hewlett-Packard printer.
· b)Construct a tree diagram and determine the sample space.Determine the probability ofselecting
· c)a Gateway computer.
Answer –The probability of selecting a Gateway computer = 4/16 = 1/4
· d) a Hewlett-Packard printer.
Answer -The probability of selecting a Hewlett Packard printer = 2/16 = 1/8
· e) a Gateway computer and aHewlett-Packard printer.
Answer- The probabilityof selecting a Gateway computer and Hewlett Packard printer = 2/16 = 1/8
Click here to see answer by Theo(3458) |
Question 476612: Hi I have included the problem for some reason I cannot attach the picture but If you can help me I will send the pic to you. I have tried to work this out but I am still needing a little bit more help so any assistance is really appreciated!!!
Question. Assume that one number from 1 to 7 is equally likely to be selected at random. Each number corresponds to one of the seven figures shown. Determine the probability of selecting a circle, given that an even number is selected.
Answer- The probability of selecting a circle given that an even number is selected = 2/3
Click here to see answer by Theo(3458) |
Question 476620: Question 1:It is known that one out of every three people entering a particular department will make at least one purchase.
a)if a random sample of n=5 persons is selected,what is the probability that:
i)two or more of them will make at least one purchase?
ii)at most four of them will make at least one purchase
b)If a random sample of n=81 persons is selected,what is the approximate probability that:
i)30 or more of them will make at least one purchase?
ii)at most 40 of them will make at least one purchase?
Click here to see answer by stanbon(57203) |
Question 476672: 1. ninety percent of licensed practical nurses are women (statistical abstract of the united states, 1992). suppose 10 licensed practical nurses are randomly selected.
A. what is the mean and standard devition?
B. what is the probability that three of the licensed practical nurses will be women?
C. what is the probability that at most 9 will be women?
D. If in fact only 3 are women, what conclusions could you draw?
Click here to see answer by stanbon(57203) |
Question 476671: 1. What is the probability of a Heart, given less than 7?
2. Are the events "King" and "less than 7" mutually exclusive? why or why not?
3. Are the events "Heart" and "less than 7" independent? why or why not? make sure you show this using the formula definition.
Click here to see answer by stanbon(57203) |
Question 476724: A lawn chair manufacturing company makes aluminum and wrought iron chairs in black or white. The ware house has the following inventory.
White aluminum 260 White Wrought Iron 1035 Black aluminum 90 and Black wrought iron 540.
A worker selects a chair from the warehouse at random. (a) find the probaility it is wrought iron (b) a wrought iron chair selected. Find the probability it is white. (c) A black chair is selected. Find the probability it is aluminum.
Click here to see answer by jorel1380(2518)  |
Question 476720: In a group of 50 men, 16 are bald, 20 have beards, and 4 are bald and have beards. A man is selected at random. (a) find the probability he is bald given he has a beard. (b) find the probability he has a beard given he is bald.
Click here to see answer by jorel1380(2518) |
Question 476720: In a group of 50 men, 16 are bald, 20 have beards, and 4 are bald and have beards. A man is selected at random. (a) find the probability he is bald given he has a beard. (b) find the probability he has a beard given he is bald.
Click here to see answer by Edwin McCravy(8879)  |
Question 476756: A bag contains a total of 8 batteries of which 3 is defective. Selecting 3 at random without replacement, determine the probability that none of the batteries you select are good.
In how many different ways can the top 8 new indie bands be ranked on a top 8 list? The top hit song for each of the 8 bands will compete to recieve monetary awards of $1000 , $500 , & $250 respectively. How many ways can the awards be given out?
Click here to see answer by Edwin McCravy(8879) |
Question 476776: An often-quoted example of an event of extremely low
probability is that a monkey types Shakespeare’s entire
play Hamlet by randomly striking keys on a typewriter.
Assume that the typewriter has 48 keys (including the
space bar) and that the monkey is equally likely to hit
any key.
A. Find the probability that such a monkey will actually
correctly type just the title of the play as his first word.
B. What is the probability that the monkey will type the
phrase “To be or not to be” as his first words?
thankyou :)
Click here to see answer by stanbon(57203) |
Question 476776: An often-quoted example of an event of extremely low
probability is that a monkey types Shakespeare’s entire
play Hamlet by randomly striking keys on a typewriter.
Assume that the typewriter has 48 keys (including the
space bar) and that the monkey is equally likely to hit
any key.
A. Find the probability that such a monkey will actually
correctly type just the title of the play as his first word.
B. What is the probability that the monkey will type the
phrase “To be or not to be” as his first words?
thankyou :)
Click here to see answer by Alan3354(30928)  |
Question 476746: 1. For a particular sample of 65 scores on a psychology exam, the following results were obtained.
First quartile = 42 Third quartile = 77 Standard deviation = 10 Range = 68
Mean = 65 Median = 68 Mode = 71 Midrange = 65
Answer each of the following:
I. What score was earned by more students than any other score? Why?
II. What was the highest score earned on the exam?
III. What was the lowest score earned on the exam?
IV. According to Chebyshev's Theorem, how many students scored between 45 and 85?
V. Assume that the distribution is normal. Based on the Empirical Rule, how many students scored between 35 and 95?
Please show all of your work.
Thank you so much
Click here to see answer by stanbon(57203) |
Question 476911: 42% of adults say cashews are their favorite kind of nut. You randomly selected 12 adults and ask each to name his or her favorite nut. Find the probability that the number who say cashews are their favorite nut is (a) exactly three, (b) at least four, and (c) most two. If convenient , use technology to find the probabilities.
(a)P(3)=____(round to the nearest thousandth )
Click here to see answer by Edwin McCravy(8879) |
Question 476935: Need help with this problem: Find the rand,standard deviation,and variance for the following sample data: 77,67,5,30,19,79,9,23,1,51,56,82,27,1,9,90 not really sure how to do any part of this need step by step if at all possible please and thank you!!!!!!!!
Click here to see answer by jim_thompson5910(28476) |
|
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
|
