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Question 422762: A report states that the average credit card debt for college seniors is $3262. The student senate at a particular college feels their seniors have a smaller debt. Their study of 50 randomly selected seniors found an average debt of $2995 with a standard deviation of $1100. Use a hypothesis test with a=.05 to determine if we can believe the students to be correct.
Click here to see answer by stanbon(57967)

Question 422891: If the probability of a person catching a cold during cold and flu season is .4, 10 people are chosen at random, what is the probability that exactly four of them will catch a cold?
I know the answer but I have no idea how to solve the problem!
thanks!
Click here to see answer by sudhanshu_kmr(1152)

Question 422870: the digits 1, 2, 3, 4, 5, and 7 are randomly arranged to form a six-digit number. Find the probability that the first and last digits are both even.
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Question 422940: Essay. According to the U. S. Census Bureau, the total 2008 U.S. population was 303,824,640. The chart below summarizes the 2008 population for five U.S. States.
State 2008 Population
Missouri 5,911,605
Pennsylvania 12,448,279
Tennessee 6,214,888
Utah 2,736,424
Washington 6,549,224

SOURCE: U. S. Census Bureau

What is the probability that a randomly selected U.S. resident did not live in Utah? Show step by step work. Round solution to the nearest thousandth.

Click here to see answer by htmentor(809)

Question 422984: determine the cumulative distribution function of a binomial random variable with n=3 and p=1/4
Click here to see answer by solver91311(17077)

Question 422965: A person's blood glucose level and diabetes are closely related. Let x be a random variable measured in milligrams of glucose per deciliter (1/10 of a liter) of blood. Suppose that after a 12-hour fast, the random variable x will have a distribution that is approximately normal with mean μ = 83 and standard deviation σ = 22. Note: After 50 years of age, both the mean and standard deviation tend to increase. For an adult (under 50) after a 12-hour fast, find the following probabilities. (Round your answers to four decimal places.)
(a) x is more than 60

(b) x is less than 110

(c) x is between 60 and 110

(d) x is greater than 140 (borderline diabetes starts at 140)
Click here to see answer by stanbon(57967)

Question 423007: Test the claim that the mean time between uses of a TV remote control by adults during commercials is not greater than 5.0 seconds. The standard deviation is known and equal 2.5 seconds.
The mean of a SRS sample of size n=650 was measured and found to be 5.25 seconds. Use significance level of 0.01.

Click here to see answer by stanbon(57967)

Question 422942: A certain drawing states that the odds of winning are 228:238. What would be the odds against winning?
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Question 423038: the ratio of male students to female students in the drama club at Campbell High School is 3:4. If the number of male students in the club is 18, predict the number of females students?
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Question 422983: Essay; show all work. A community 5K run will award $50 to the winner. 60 people enter the race, and they each pay an entry fee of $20. Assuming they are all equally likely to win, what is a fair price for the competition? Round to the nearest cent.
Click here to see answer by stanbon(57967)

Question 423133: Assuming that each of the 52 cards in an ordinary deck has a probability of 1/52 of being drawn, what is the probability of drawing a black ace?

Click here to see answer by sudhanshu_kmr(1152)

Question 423126: 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 red or a blue figure, given that an even number is selected.Show work please
1= yellow circle
2= red triangle
3= blue square
4= red square
5= yellow circle
6= blue triangle
7= red circle

Click here to see answer by sudhanshu_kmr(1152)

Question 423194: Hello,
I think this is a probability problem... if it is not considered probability than i am sorry.
During boot camp, the drill sergeant measured the weight of the men in his unit. the average weight of the men was 142 pounds and the standard deviation was 14 pounds. the data is normally distributed. if there are 100 men in the unit, how many men would be expected to weigh less than 128 pounds?
The 100 men part of the problem threw me off. thanks for all of your help :)
Click here to see answer by stanbon(57967)

Question 423183: Four managers, five engineers and one lawyer are in a meeting when a message arrives for one of them. of these people, three managers, two engineers and the lawyer are women. find the probability of each of the following events:
A) The message is for a man.
B) The message is not for a male engineer.
Click here to see answer by stanbon(57967)

Question 423349: Evaluate: 6^C4
Click here to see answer by jsmallt9(3296)

Question 423266: If 3 books are picked at random from a shelf containing 5 novels, 3 books of poems, and a dictionary. What is the probability that
(a) the dictionary is picked
(b) 2 novels and 1 book of poems are selected?
Thanks for the help!
Click here to see answer by sudhanshu_kmr(1152)

Question 423430: do i take .80/0, .80/1, .80/2, .80/3, .80/4 to find my probabilty???? If i am in the wrong thought process please help set me straight.
First fill in this table (Round to 3 decimals)
BINOMIAL Probability Distribution
N=4 P=.80
Number of successes(x) probability
0 ?
1 ?
2 ?
3 ?
4 ?
2a) Mean= expected value for the # of sales= ____
Variance = _________
Use the table to answer the following questions:
2b) What is the probability that atleast1 policy is sold?
2c) What is the probability that the representative sells more than 1 policy?

Click here to see answer by ewatrrr(10682)

Question 423443: Suppose you and your 2 friends are part of a group of 15 potential jurors in court. If 3 people from this group are to be chosen at random for the last remaining seats on the jury, what is the probability that you and your 2 friends are the last 3 people chosen?
Click here to see answer by ewatrrr(10682)

Question 423444: heres the question i need help with please.
The Key Refining Company, referred to earlier, determined that 20% of its customers do not pay their bill by the due date. What is the probability that for a sample of 80 customers, less than 18 will not pay their bill by the due date?
Can you use the normal approximation to the binomial on this problem? Why or why not? What constraints must be met?

My theory is no normal curve i solved this by using
p=80
80 (.80)plus or minus 5
80 (.20) plus or minus 5
am i close?????

Click here to see answer by stanbon(57967)

Question 293512: The average age of residents in a large residential retirement community is 69 years with standard deviation 5.8 years. A simple random sample of 100 residents is to be selected, and the sample mean age of these residents is to be computed.
The probability that the average age, of the 100 residents selected is more than 70 years is...?
Click here to see answer by marissaellison(1)

Question 423637: how to calculate standard deviation square foot?
Click here to see answer by stanbon(57967)

Question 423558: what is the probability of drawing an even card from a deck of cards marked 1-10, then drawing a 5?
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Question 423557: Evaluate 12C8
a. 24
b. 1680
c. 11880
d. 495

Click here to see answer by stanbon(57967)

Question 423556: Given that P(A) = 0.2 and P(B) = 0.8, and P(A and B) = 0.16, determine P(B|A).
a. 0.40
b. 0.20
c. 0.16
d. 0.80

Click here to see answer by stanbon(57967)

Question 423549: Show all work. Mary purchased a package of 13 different plants, but she only needed 9 plants for planting. In how many ways can she select the 9 plants from the package to be planted?
Click here to see answer by stanbon(57967)

Question 423704: 70% OF THE STUDENT BODY OF A very large post secondary institution is female. in a random sample of 12 students what is the probability that
a)at most half will be females?
b) more than 7 will be femels?
c) fewer than 3 will be males
Click here to see answer by stanbon(57967)

Question 423697: ACCORDING TO A RECENT STUDY 38% OF ALL WOMEN WILL SUFFER A HIP FRACTURE BECAUSE OF OSTEOPOROSIS BY THE AGE OF 85. IF SIX WOMEN AGED 85 ARE RANDOMLY SELECTED WHAT IS THE PROBABILITY THAT
A) NONE OF THEM WILL SUFFER (OR HAS SUFFERED) A HIP FRACTURE DUE TO OSTEOPOROSIS
b) AT LEAST 4 OF THEM WILL SUFFER (OR HAS SUFFERED) A HIP FRACTURE DUE TO OSTEOPOROSIS
c)FEWER THAN TWO OF THEM WILL SUFFER (OR HAVE SUFFERED) A HIP FRACTURE DUE TO OSTEOPOROSIS
Click here to see answer by stanbon(57967)

Question 423725: How many different arrangements of three coins can be made if you have a penny, a nickel, a dime, a quarter, and a silver dollar?
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Question 423728: A die is rolled three times. what is the P(no 5s and no 3s)?
Click here to see answer by stanbon(57967)

Question 423803: a ceramic jar contains 48 quarters and 21 dimes. If two coins are randomly drawn in sucession, without replacement, what is the probaility that the total value of the coins is $.20

Click here to see answer by htmentor(809)

Question 423830: If a standard deck of 52 cards are placed on a table faced down, what is the probability of getting a face card on ace?
Click here to see answer by Alan3354(31530)

Question 423914: Consider a population with the mean = 43 and sd = 5.2.
Calculate the z-score for an xbar of 46.5 from a sample of size 35.
Click here to see answer by ewatrrr(10682)

Question 423926: I have not a clue where to start with this, any help?
• a) Explain how to calculate 500/499 without a calculator.
• b) Evaluate 500/499

Click here to see answer by htmentor(809)

Question 424012: State College is evaluating a new English composition course for freshmen. A random sample of n=25 freshmen is obtained and the students are placed in the course during their first semester. One year later, a writing sample is obtained for each student and the writing samples are graded using a standardized evaluation technique. The average score for the sample is M=76. For the general population of college students, writing scores form a normal distribution with a mean of m=70.
a. If the writing scores for the population have a standard deviation of σ=20, does the sample provide enough evidence to conclude that the new composition course has a significant effect? Assume a two- tailed test with α=.05.

Click here to see answer by stanbon(57967)

Question 423732: From a group of 7 men and 5 women...
a. How many committees of 4 can be formed?
b. How many ways can a President, vice president and secretary be chosen?
c. How many committees of 2 women and 3 men can be formed?
Click here to see answer by stanbon(57967)

Question 423857: How many 5 digit numbers greater or equal to 15,000 are there?
Click here to see answer by robertb(4012)

Question 424087: suppose 5 cards are drawn at random from a pack of 52 cards .If all cards are red what is the probability that all of them are hearts?
Click here to see answer by stanbon(57967)

Question 424083: Suppose X is a normally distributed random variable with the mean=10.1 and standard deviation=3.6. Find each of the following probabilities:
P(10.1<=x<=15.6)
and
P(x>=8)

Click here to see answer by stanbon(57967)

Question 424044: Can Iget some help with this problem please.I tried some of it but get stuck. Thanks Kim
The recovery rate from the flu is 0.9. If 4 people get the flu waht is the probabilty that
all will recover?
0.9^4=.656
at least 2 will recover?
C(4,2)=6 ways
0.9*0.9*0.1*0.1=0.0081
exactly 2 will recover?

Click here to see answer by stanbon(57967)

Question 424111: Can you please check my answer Thanks
4. An identification code is to consist of seven letters followed by three digits. How many different codes are possible if repetition is permitted? (Points : 2)
26 is the number in the alphabet 10 is the number from 0-9 26^7*10^3= 8031810176*1000=8031810176000 different codes
5. Show all work. A disc jockey has 10 songs to play. Seven are slow songs, and three are fast songs. Each song is to be played only once. In how many ways can the disc jockey play the 10 songs if
• The songs can be played in any order. The 1st is 1 of 10, then 1 of 9, 8, 7 etc
= 10*9*8*7... = 10!
-------------------
* The first song must be a slow song and the last song must be a slow song.
The 1st is 1/7, the last is 1/6. The other 8 are 1 of 8, 7, 6, 5, 4,The first song must be a slow song and the last song must be a slow song. The 1st is 1/7, the last is 1/6. The other 8 are 1 of 8, 7, 6, 5, 4, 3, 2, 1= 7*6*(8!)
• The first two songs must be fast songs. 3*2*(8!)
(Points : 3)

Click here to see answer by sudhanshu_kmr(1152)

Question 424134: Stuck on this one!
I select a number from the 12 numbers 1 through 12. Each number is equally likely to be chosen. Let A be the event: I chose an even number. Let B be the event: I chose a number less than or equal to 5.
Find each based on one selection from the 12 numbers.
a) P(A occurred or B occurred)
b) P(A occurred and B occurred)
c) P(A occurred given that B occurred

I think c is P(A|B)=2/5 but not sure the rest.

Click here to see answer by ewatrrr(10682)

Question 424256: Show all work. A disc jockey has 7 songs to play. Three are slow songs, and four are fast songs. Each song is to be played only once. In how many ways can the disc jockey play the 7 songs if
• The songs can be played in any order.
• The first song must be a slow song and the last song must be a slow song.
• The first two songs must be fast songs.

Click here to see answer by stanbon(57967)

Question 424245: Please explain this
Describe what a type I and type II error would be for each of the following null hypotheses:
: There is no good plan for the Iraq war.
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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, 21241..21285, 21286..21330, 21331..21375, 21376..21420, 21421..21465, 21466..21510, 21511..21555