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Question 309707: Answer the following questions regarding the normal, standard normal and binomial distributions.

(A) Why can the normal distribution be used as an approximation to the binomial distribution?

(B) What conditions must be met in order to use the normal distribution to approximate the binomial distribution?

(C) How does the standard normal distribution differ from the normal distribution
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Question 309706: Assume that the population of heights of female college students is approximately normally distributed with mean m of 68 inches and standard deviation s of 2.75 inches. A random sample of 16 heights is obtained. Show all work.

(A) Find the proportion of female college students whose height is greater than 69 inches.

(B) Find the mean and standard error of the distribution

(C) Find
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Question 309702: In a certain lottery, 4 numbers between 1 and 10 inclusive are drawn. These are the winning numbers. How many different selections are possible? Assume that the order in which the numbers are drawn is not important.
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Question 309546: 3. Your High School basketball team’s starting 5 players are listed at the following heights:
5’8” (68 inches)
5’10” (70 inches)
6’1” (73 inches)
6’2” (74 inches)
7’4” (88 inches)
What is the median height on this team?
What is the mean height?
If you wanted to lull the opponent into a false sense of security, which statistic would you publish? Why?
If you wanted to intimidate your opponent, which statistic would you publish? Why?

Click here to see answer by stanbon(57203)

Question 309818: 2. Assume the body temperatures of healthy adults are normally distributed with a mean of 98.20 °F and a standard deviation of 0.62 °F (based on data from the University of Maryland researchers).
a. If you have a body temperature of 99.00 °F, what is your percentile score?
b. Convert 99.00 °F to a standard score (or a z-score).
c. Is a body temperature of 99.00 °F unusual? Why or why not?
d. Fifty adults are randomly selected. What is the likelihood that the mean of their body temperatures is 97.98 °F or lower?
e. A person’s body temperature is found to be 101.00 °F. Is the result unusual? Why or why not? What should you conclude?
f. What body temperature is the 95th percentile?
g. What body temperature is the 5th percentile?
h. Bellevue Hospital in New York City uses 100.6 °F as the lowest temperature considered to indicate a fever. What percentage of normal and healthy adults would be considered to have a fever? Does this percentage suggest that a cutoff of 100.6 °F is appropriate?

This is one question of many on a Statistics quiz due monday night for me. I would greatly appreciate any and all help provided. Thank you in advance!
Click here to see answer by stanbon(57203)

Question 309850: 1. Among cofee drinkers, men drink of 3.2 cups per day with a standard deviation of 0.8 cups. Assume the number of coffee drinks per day follows a normal distribution.
a. What proportion drink 2 cups per day or more?
b. what proportion drink no more than 4 cups per day?
c. If the top 5% coffee drinkers are considered heavy coffe drinkers, what is the minimum number of cups by a heavy coffee drinker? (hint find the 95th percentile.)
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Question 309704: The diameters of oranges in a certain orchard are normally distributed with a mean of 7.3 inches and a standard deviation of 0.80 inches. Show all work.

(A) What percentage of the oranges in this orchard have diameters less than 6.7 inches?

(B) What percentage of the oranges in this orchard are larger than 7.20 inches?

(C) A random sample of 100 oranges is gathered and the mean diameter obtained was 7.20. If another sample of 100 is taken, what is the probability that its sample mean will be greater than 7.10 inches?

(D) Why is the z-score used in answering (A), (B), and (C)?

(E) Why is the formula for z used in (C) different from that used in (A) and (B)?

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Question 309911: Suppose your vehicle is licensed in a state that issues license plates that consist of three digits (between 0 and 9) followed by three letters (between A and Z). If a license number is selected randomly, what is the probability that yours is the one selected?
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Question 309892: waiting times
single line: 6.5, 6.6, 6.7, 6.8, 7.1, 7.3, 7.4, 7.7, 7.7, 7.7
individual line: 4.2, 5.4, 5.8, 6.2, 6.7, 7.7, 7.7, 8.5, 9.3, 10.0
a)Find the mean, median, mode, variance, standard deviation, and range of each data set. Which appears to be the fastest?
b)Perform a hypothesis test to see if one method appears to be efficient than the other. (Hint: test 2 means). Show the null and alternative hypotheses, the critical value at 0.05, the test statistic, and the P-value. Lastly show (explain) your conclusion.
Click here to see answer by stanbon(57203)

Question 310013: An important factor in selling a residential property is the number of people who look through the home. A sample of 15 homes recently sold in the Buffalo, New York, area revealed the mean number looking through each home was 24 and the standard deviation of the sample was 5 people. Develop a 98 percent confidence interval for the population mean.
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Question 310174: consider a test with 50 multiple-choice questions, each with 5 options. If students guess radomly on the test, what is the expected mean and standard deviation?
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Question 310151: If P(A)=0.80, P(B)=0.70 AND P(A or B)=0.90, then compute P( A and B).
Thank you,
Chrissie
Click here to see answer by stanbon(57203)

Question 310140: a bookshelf contains six mysteries and three biographies. two books are selected at random without replacement.
a. what is the probability that both books are mysteries?
b. what is the probability that one book is a mystery and the otehr is a biography?
Click here to see answer by stanbon(57203)

Question 310137: Evolutionary theories often emphasize that humans have adapted to their physical
environment. One such theory hypothesizes that people should spontaneously
follow a 24-hour cycle of sleeping and waking—even if they are not exposed to
the usual pattern of sunlight. To test this notion, eight paid volunteers were
placed (individually) in a room in which there was no light from the outside and
no clocks or other indications of time. They could turn the lights on and off as
they wished. After a month in the room, each individual tended to develop a
steady cycle. Their cycles at the end of the study were as follows: 25, 27, 25, 23, 24, 25, 26, and 25.
Using the .05 level of significance, what should we conclude about the
theory that 24 hours is the natural cycle? (That is, does the average cycle length under these conditions differ significantly from 24 hours?) (a) Use the steps of hypothesis testing. (b) Sketch the distributions involved. (c) Explain your answer to someone who has never taken a course in statistics.

Click here to see answer by stanbon(57203)

Question 310096: construct the indicated confidence interval for the population mean mu using a t distriution, s=10, c= .80, x bar =114, n=9
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Question 310138: Twenty students randomly assigned to an experimental group receive an
instructional program; 30 in a control group do not. After 6 months, both groups
are tested on their knowledge. The experimental group has a mean of 38 on the
test (with an estimated population standard deviation of 3); the control group
has a mean of 35 (with an estimated population standard deviation of 5). Using
the .05 level, what should the experimenter conclude? (a) Use the steps of
hypothesis testing, (b) sketch the distributions involved, and (c) explain your
answer to someone who is familiar with the t test for a single sample but not
with the t test for independent means.

Click here to see answer by stanbon(57203)

Question 310301: Find the cubic polynomial which takes the following values y(0) = 1, y(1) = 0, y(2) = 1 and y(3) = 10 . Hence obtain the value of y(0.5).
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Question 310300: this is my id poojitha.k.n@gmail.comFind the cubic polynomial which takes the following values y(0) = 1, y(1) = 0, y(2) = 1 and y(3) = 10 . Hence obtain the value of y(0.5).
Click here to see answer by stanbon(57203)

Question 310296: A box contains 74 brass washers, 86 steel washers and 40 aluminum washers, three washers are drawn at random from the box without replacement. Determine the probability that all three are steel washers.

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Question 310248: How many 7 card hands having exactly 3 Aces, 4 other cards can be dealt?

Five coins are tossed. Find the Probability of each event.
a. At least one comes up tails.

b. Exactly two come up tails

Click here to see answer by stanbon(57203)

Question 310223: A group of files in a medical clinic classifies the patients by gender and by the type of diabetes ( 1 or 2). below is the number in each classification.
type 1 type 2
male 42 21
female 49 28
Find the probability that the selected individual is a female and type 2? Is the answer 1/5
Find the probability that the selected individual is a male and type 1? Is the answer 3/10
Find the probability that the individual gets type 1 knowing that the individual is a male?
Thank you,
Chrissie

Click here to see answer by stanbon(57203)

Question 310258: P(6 < x-bar < 8) = P(-0.3514 < z < +0.3514) = 0.2747
How did you get the 0.2747
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Question 310321: Lock combinations are made by using 4 digits. How many different lock combinations can be made if repetition of digits is allowed?
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Question 310308: you are taking an online algebra quiz in which 6 questions are randomly selected from a test bank counting 50 questions. How many versions of the quiz are possible?
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Question 310228: When it is not raining, the probability of the Buchanan Bears winning a football game is 2/3. When it is raining the probability of the Bears winning is 3/15. The probability of rain on any day in December is 3/4.
What is the probability of the Bears winning on December 5?

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Question 310222: find the number of possible 5-card hands taken from a standard 52-card deck that contain 2 aces and 3 cards that are not aces
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Question 310197: Drawing a Card If one card is drawn from a deck, find the probability of getting these results:
a. An ace
b. A diamond
c. An ace of diamonds
d. A 4 or a 6
e. A 4 or a club
f. A 6 or a spade
g. A heart or a club
h. A red queen
i. A red card or a 7
j. A black card and a 10

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Question 309996: Two cards are drawn without replacement from an ordinary deck of 52 playing cards. What are the odds against drawing two red cards?
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Question 310465: What is the probability of rolling a red and a green number cube and getting:
A sum of 7 OR 11?
A prime number on red OR a two one green?
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Question 310423: Bellevue Hospital in New York City uses 100.6 °F as the lowest temperature considered to indicate a fever.

a. (0.1 point) What percentage of normal and healthy adults would be considered to have
a fever? :

b. (0.1 point) Does this percentage suggest that a cutoff of 100.6 °F is appropriate?
Click here to see answer by stanbon(57203)

Question 310501: A hat contains 20 names, 9 of which are female. If eight names are randomly drawn from the hat, what is the probablility that at least six male names are drawn?
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Question 310504: Find P(the trip will take 25 min)
time in minutes: 20 25 30
____________________________
number of trips: 4 8 2
Click here to see answer by Fombitz(13828)

Question 310526: Based on the information given for each of the following studies, decide
whether to reject the null hypothesis. For each, give (a) the Z-score cutoff (or
cutoffs) on the comparison distribution at which the null hypothesis should be
rejected, (b) the Z score on the comparison distribution for the sample score, and
(c) your conclusion. Assume that all populations are normally distributed
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Question 310535: A realty company has 100 homes listed for sale.Some of thses homes have fire places, some have garages, and some have neither.What is the probability that the home selected does not have a fire place?
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Question 310550: A restaurant offers the following choices for breakfast:
Eggs: scrambled, fried or poached
Meat: bacon, sausage, or ham
Toast: wheat, white, rye or pumpernickel
The Super Breakfast allows you to select two items for the meat list. How many breakfast combinations are possible if you select one each of the eggs and toast choices and two different meat choices?
Create sample space????????
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Question 310570: P(A)=0.31
P(B given A)=0.8
P(A and B)=(help)
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Question 310547: A restaurant offers the following choices for breakfast:
Eggs: scrambled, fried, or poached
Meat: bacon, sausage, or ham
Toast: wheat, white, rye or pumpernickel

How many different breakfast combinations are possible if one item is selected from each list of eggs, meat, & toast choices?
I know I need to create the sample space but not sure how to get started.....
Click here to see answer by user_dude2008(1861)

Question 310548: You have a bag of Skittles. The bag contains 50 Skittles. There are 5 colors, and 10 of each color. What is the probability of choosing the same color 3 times in a row? (You eat each Skittle.) Express your answer as a fraction in simplest form.
Click here to see answer by Fombitz(13828)

Question 310543: You are trying to collect all nine baseball cards for an All-Star team. Each package of cards he can buy has one card of a member of the team. The cards are equally distributed among all the packages. How could you use a simulation to estimate the number of packages of cards you will need to buy to get all nine cards?
Click here to see answer by stanbon(57203)

Question 310652: 2. A local tire store suspects that the mean life of a new discount tire is less that 39,000 miles. To check the claim, the store selects randomly 18 of these new discount tires. When they are tested, it is found that the mean life is 38,250 miles with a sample standard deviation s = 1200 miles. Assume the distribution is normally distributed.

a. Use the critical value t0 method from the normal distribution to test for the population mean . Test the company’s claim at the level of significance  = 0.05.
(References: example 1 though 5 pages 397 - 401, end of section exercises 23 – 28 pages 404 - 405) (5 points)

1. H0 :
Ha :
2.  =
3. Test statistics:
4. P-value or critical z0 or t0.
5. Rejection Region:
6. Decision:

7. Interpretation:

b. Use the critical value t0 method from the normal distribution to test for the population mean m. Test the company’s claim at the level of significance a = 0.01
(References: example 1 though 5 pages 397 - 401, end of section exercises 23 – 28 pages 404 - 405) (5 points)

1. H0 :
Ha :
2. a =
3. Test statistics:
4. P-value or critical z0 or t0.
5. Rejection Region:
6. Decision:
7. Interpretation:

Click here to see answer by stanbon(57203)

Question 310647: 5. A researcher claims that the average age of people who buy lottery tickets is 65. A sample of 30 is selected and their ages are recorded as shown below. The standard deviation is 14. At α = 0.05 is there enough evidence to reject the researcher’s claim? Show all work.
49
63
80
52
22
80
72
56
70
56

24
46
70
74
70
61
65
71
39
74

79
76
71
49
62
68
71
67
69
45

Click here to see answer by Edwin McCravy(8878)

Question 310721: If the Z score sample of 35 employees is 2.0, what is their weekly salary, given that the population mean slaray is $1,000 per week and the standard deviation is $100?
Click here to see answer by Fombitz(13828)

Question 310712: There are 5 roads from Albany to Briscoe, 6 from Briscoe to Chadwick, and 3 from Chadwick to Dover. How many different routes are there from Albany to Dover via Briscoe to Chadwick?
Click here to see answer by nyc_function(2733)

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