Tutors Answer Your Questions about Probability-and-statistics (FREE)
Question 375925: Assume that blood pressure readings are normally distributed with mean=120 and standard deviation =8. A blood pressure reading of 145 or more may require medical attention. What percentage of people have a blood pressure reading greater than 145?
Click here to see answer by robertb(4012)  |
Question 375884: A normal distribution consist of 100 scores with a mean of 65 and a standard deviation of 5. How many scores are above 70 and how many scores are below 55?
Please break it down step by step, because I am not understanding. I think I got the 2nd half right, but I cannot come up with the 1st part with scores being above 70.
Thanks
Kerry
Click here to see answer by stanbon(57290) |
Question 375967: Suppose we have a set of blood pressures with a mean of 120 Systolic, and a sample standard deviation of 15 points. If we assume a normal distribution of Systolic blood pressures, then between what two values can we be assured 99.7% of all Systolic blood pressures will lie?
Click here to see answer by robertb(4012)  |
Question 375981: A dart is thrown randomly and stick on the circular dart board with 26 partitions. determine the probability that the dart lands on the area marked with a number greater than four and less than or equal to 13.
Click here to see answer by edjones(7569)  |
Question 375904: Copykwwik has four photocopy machines A B C D The probability that a given machine will break down on a particular day is
P(a)=1/50 P(B)= 1/60 P(C)= 1/75 P(D)= 1/40
assuming independence what is the probability on a particular day that
a) all four machines will break down
b) none of the machines will break down
Click here to see answer by Fombitz(13828)  |
Question 376017: USA Today reports that about 25% of all prison parolees become repeat offenders. Alice is a social worker whose job is to counsel people on parole. Let us say success means a person does not become a repeat offender. Alice has been given a group of four parolees.
(a) Find the probability P(r) of r successes ranging from 0 to 4.
(b) What is the expected number of parolees in Alice's group who will not be repeat offenders? What is the standard deviation?
Click here to see answer by edjones(7569)  |
Question 375961: in a online survey for talbots of 1095 women ages 35 yr and older the participants were asked what article of clothing women most want to fit perfectly a summary of the results of thesurvey follows
article of clothing responedents
jeans 470
black pantsuit 307
cocktail dress 230
white shirt 22
gown 11
other 55
if a women who participated in the survey is chosen at random what is the probabality that she most wants A) jeans to fit perfectly or b) a black paintsuit,or cocktail dress to fit perfectly
Click here to see answer by edjones(7569)  |
Question 375910: in a school,45% of the students are boys and 55% are girls. in this school, 12% of the boys are left handed and 9% of the girls are left handed. a student is to be chosen at random using a tree diagram
a) calculate the probability that the student is not left handed
Given that the student chosen is left handed,
b)calculate, to 3 significant figures,the probabillity that the student is a girl
Click here to see answer by edjones(7569)  |
Question 375906: Elaine is 65 years old, and has the probability that she will be alive in 10 years is 76%. John is 35, and the probability that he will be alive in 10 years is 90%. What is the brobability they will be both alive in 10 years?
Click here to see answer by edjones(7569)  |
Question 376154: A number cube labeled with number 1,2,3,4,5 and 6 is tossed. what are the odds in favor of the cube showing an odd number??
When two balanced dice are rolled, there are 36 possible outcomes. What is the Probability that the sum of the numbers on the dice is 6 or 11?
Click here to see answer by Fombitz(13828)  |
Question 375965: 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. What SAT I score within the population would have a percentile rank of approximately 97.5? Show all work as to how this is obtained.
Click here to see answer by ewatrrr(10682)  |
Question 376225: Describe the weight of the top 10% of the babies born with each gestation period.
a. 37 to 39 weeks - mean birth weight=7.31lb, standard deviation=1.09lb
b. 42 weeks and over - mean birth weight=7.61lb, standard deviation=1.11lb.
Click here to see answer by ewatrrr(10682)  |
Question 376263: Student Financial Aid In a recent year 8,073,000 male
students and 10,980,000 female students were enrolled
as undergraduates. Receiving aid were 60.6% of the
male students and 65.2% of the female students. Of
those receiving aid, 44.8% of the males got federal aid
and 50.4% of the females got federal aid. Choose 1
student at random. (Hint: Make a tree diagram.) Find
the probability that the student is
a. A male student without aid
b. A male student, given that the student has aid
c. A female student or a student who receives federal
Click here to see answer by ewatrrr(10682)  |
Question 375919: The distribution of cholesterol levels in teenage boys is approximately normal with the mean of 170 and Sd =30. Levels above 200 warrant attention. Find the probability that a teenage boy has a cholesterol level greater than 225.
Click here to see answer by Fombitz(13828)  |
Question 376308: The following time series data represent the yearly amounts spent on advertising (in millions of dollars) by a large toy company:
19.2, 20.7, 25.1, 23.9, 27.0, 23.9
This series of data begins in year 1997 (i.e., time period t=1 corresponds to 1997). Using regression analysis, a linear trend line of the form Tt=19.18+1.18t was fit to the data. Using this information, generate a forecast for the total yearly amount of money that will be spent on advertising in 2010 .
Click here to see answer by user_dude2008(1861) |
Question 376288: Cable Television In 2006, 86% of U.S. households had
cable TV. Choose 3 households at random. Find the
probability that
a. None of the 3 households had cable TV
b. All 3 households had cable TV
c. At least 1 of the 3 households had cable TV
Click here to see answer by edjones(7569)  |
Question 376285: The probability that a given tourist goes to amusement park is 0.47, and the probability that she goes to the water park 0.58. if the probabitiy that she goes to either the water park or the amusement park is 0.95, what is the probability that she visit both of the parks on vacation
Click here to see answer by edjones(7569)  |
Question 376285: The probability that a given tourist goes to amusement park is 0.47, and the probability that she goes to the water park 0.58. if the probabitiy that she goes to either the water park or the amusement park is 0.95, what is the probability that she visit both of the parks on vacation
Click here to see answer by robertb(4012)  |
Question 376281: the lenghts of pregnancies of humans are normally distributed with a mean of 268 days and a standard deviation of 15 days. A baby is premature if born 3 weeks early. What percentage of babies are born prematurely?
Click here to see answer by robertb(4012)  |
Question 376335: 1. an ice chest contains 3 cans of apple juice, 5 cans of grape juice, 8 cans of orange juice and 2 cans of pineapple juice. You randomly select 3 cans succession. find the probability of selecting no grape juice?
2. the winner of a raffle will receive a new car. If 10,000 raffle tickets were sold and you purchased 25 tickets, what are the odds against your winning the car?
3. If you are given odds 3 to 7 in favor of winning a bet, what is the probability of winning the car?
Click here to see answer by edjones(7569)  |
Question 376507: * A lot of 75 washers contains five in which the variability in thickness around the circumference of the washer is unacceptable. A sample of 10 washers is selected at random, without replacement.
i) What is the probability that at least one unacceptable washer is in the sample?
ii) What is the probability that at most one unacceptable washer is in the sample?
Click here to see answer by edjones(7569)  |
Question 376519: * The probability of a successful assembly of a product in a manufacturing process is 0.8.
i) What is the probability that the first successful assembly requires exactly four trials?
ii) What is the probability that the first successful assembly requires at least four trials?
iii) What is the probability that the first successful assembly requires at most four trials?iv) What assumptions did you make, if any, to solve this problem?
Click here to see answer by Edwin McCravy(8901)  |
Question 376708: a mining company is considering two sites on which to dig, described as follows
site A- profit if diamonds are found $70 million. Loss if no diamonds are found $25 million. probability of finding diamonds 0.2
site B- profit if diamonds are found $110 million. loss if no diamonds are found $16 million. probabilty of finding diamonds 0.1
What is the expected profit for each site?
Click here to see answer by solver91311(16877)  |
|
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
|