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Question 203648: A card is drwn from a well-shuffled deck of 52 cards. What is the probability of drwing a face card or a 3?
Click here to see answer by stanbon(57219)

Question 203671: A manufacturer claims that at least 99% of all his products meet the minimum government standards. A survey of 500 products revealed ten did not meet the standard.
Conduct the standard hypothesis test procedure and answer the following:
What is the null hypothesis?
What is the alternate hypothesis?
What is the critical value if a = .01?
What is the z-statistic? ?
What is your decision ?? Do the products meet the government standards?

Click here to see answer by stanbon(57219)

Question 203685: The number of older consumers in the United States is growing and they are becoming an even bigger economic force. Many feel overwhelmed when confronted with the task of selecting investments, banking services, health care providers, or phone service providers. A telephone survey of 1,900 older consumers found that 27% said they didn’t have enough time to be good money managers (“seniors confused by financial choices – study,” msnbc.com, May 6, 2004).
a) Construct a 95% confidence interval for the population proportion of older consumers that don’t think they have enough time to be good money managers.
b) Interpret the interval in (a)

Click here to see answer by stanbon(57219)

Question 203650: Estimate the probability of the event:
the data set represents the income levels of the members of a country club. Estimate the probability that a randomly selected member earns at least $91,000. round you answers to the nearest tenth.
107,000; 123,000; 85,000; 131,000; 88,000; 107,000; 91,000; 79,000; 147,000; 187,000; 82,000; 99,000; 139,000; 88,000; 123,000; 115,000; 91,000; 155,000; 76,000; 115,000
Click here to see answer by rfer(12644)

Question 203771: a weld inspector in a shipyard knows that 5% of all welds done will be substandard. if he checks 300 out of 7500 welds completed, what is the probablility that he will find between 10 and 20 substandard welds?
I know 5% of total 7500 welds yields 375 substandard welds, not sure how to figure.
Click here to see answer by rfer(12644)

Question 203798: A certain jar consists of seven green marbles, five black and four red marbles. If three marbles are drawn at random, find the probability that all three marbles are the same color.

If needed, round to two decimal places.

Click here to see answer by stanbon(57219)

Question 203799: Hi Please help me with this problem. It is really hard and I'm not sure if I should be using a z-test or a t-test. Thanks for helping.

Reports say that the average teenager spends $39 during a shopping trip to the mall. The promotions director of a local mall has used a variety of strategies to attract area teens to his mall, including live bands and teenage appreciation days that feature special bargains for this age group. He believes teen shoppers at his mall respond to his promotional efforts by shopping there more often and spending more when they do. Mall management decides to evaluate the promotions director's success by surveying a simple random sample of 45 local teens and finding out how much they spend on their most recent shopping visit to the mall. Use a suitable hypothesis test in examining whether the mean mall shopping expenditure for teen sin this area might be higher than for US teens as a whole. Identify and interpret the p-value for the test. Using the 0.025 level of significance what conclusion do you reach?
Spent
40.33
46.06
37.98
50.81
19.03
59.36
31.81
45.98
45.07
40.94
51.06
52.36
45.68
72.28
37.07
40.57
17.44
55.28
41.26
52.34
8.39
61.54
49.94
59.13
44.99
55.47
42.17
26.79
37.30
56.98
36.51
52.23
46.55
52.06
11.84
57.28
51.73
50.24
66.58
18.39
19.15
37.50
22.17
48.98
40.63

Click here to see answer by stanbon(57219)

Question 203867: If the inspection division of a county weifhts and measures department wants to estimate the mean amount of soft-drink fill in 2-liter bottles to with +/- 0.01 liter with 95% confidence and also assumes that the standard deviation is 0.05 liter, what sample size is needed?
Click here to see answer by stanbon(57219)

Question 203865: The following data represents the monthly service fee in dollars if a customer’s account falls below the minimum required $1,500 balance for a sample of 26 banks for direct-deposit customers. Bancost2
12 8 5 5 6 6 10 10 9 7 10 7 7
5 0 10 6 9 12 0 5 10 8 5 5 9
a) Construct a 95% confidence interval for the population mean monthly service fee in dollars if a customer’s account falls below the minimum required balance.
b) Interpret the interval constructed in (a)

Click here to see answer by stanbon(57219)

Question 203877: If the manager of a paint supply store wants estimate the mean amount of paint in a 1-gallon can to within +/- 0.004 gallon with 95% confidence and also assume that the standard deviation is 0.02 gallon, what sample size is needed?
Click here to see answer by stanbon(57219)

Question 203953: you are dealt 2 cards successively (without replacement) from a shuffled deck of 52 playing cards. Find the probability that the first card is a king and the second card is a queen.
Click here to see answer by rfer(12644)

Question 203956: I have two probability questions.
1) from 8 shirts, 6 pair. of slacks, and 4 jackets how many different outfits can be made?
2) 9 points are placed on a circle, how many triangles can be formed using these points, three at a time as vertices?
thanks for the help.
Click here to see answer by stanbon(57219)

Question 203954: A bag contains 6 cherry, 3 orange and 2 lemon candies. You reach in and take 3 pieces of candy at random. What is the probability that you have at least 2 orange candies?
Click here to see answer by scott8148(6628)

Question 203952: you are dealt 2 cards successively (without replacement) from a shuffled deck of 52 playing cards. Find the probability that the first card is a king and the second card is a queen.
Click here to see answer by josmiceli(9649)

Question 203977: 1.find all real values of 'w' for which the statement
C(w+1,2)=9•C(w,1) is true.
2. while shooting arrows, William can hit an apple 9 out of 10 times. what is the probability that he will hit it exactly 4 out of the next 7 times.
*both of them were really hard for me to figure out. I appreciate your help.
Click here to see answer by stanbon(57219)

Question 204004: A family has five children. The probability of having a girl is 1/2. What is the probability of having no girls?
I came up with two answers but am unsure of either. This is for a take home exam and I musy show the work. Please help! Class is at two o'clock today!!!
Click here to see answer by stanbon(57219)

Question 204003: If two cards are drawn without replacement from a deck, find the probability that the second card is a spade, given that the first card was a spade.
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Question 203938: 8.46 A random sample of 10 miniature Tootsie Rolls was taken from a bag. Each piece was weighed on
a very accurate scale. The results in grams were
3.087 3.131 3.241 3.241 3.270 3.353 3.400 3.411 3.437 3.477
(a) Construct a 90 percent confidence interval for the true mean weight. (b) What sample size
would be necessary to estimate the true weight with an error of } 0.03 grams with 90 percent confidence?
(c) Discuss the factors which might cause variation in the weight of Tootsie Rolls during
manufacture. (Data are from a project by MBA student Henry Scussel.

Click here to see answer by stanbon(57219)

Question 204089: determine how many card holders should be sampled.
what is the required sample size needed to be able to estimate the mean dollars that credit card holders will spend each month. Within plus or minus $10.00 of the true mean with a 98% confidence level? Standard deviation is thought to be $500.00. how many card holders should be sampled? We then find out it will cost $5.00 per sample and the company is only planning to spend $10,000.00 on the sample. What will the trade off be when you lower the sample to $10,000.00 to meet their budget?
Click here to see answer by stanbon(57219)

Question 204147: The odds against Lightning winning the third race are 9:4. If Sally places an $8 bet on Lightning to win and Lightning wins, find Sally’s net winnings
A) $2.25 B) $36 C) $18.00 D) $9.00 E) $72

Click here to see answer by Theo(3458)

Question 204216: An independent television station airs a movie-of-the-day every Tuesday and Thursday. Their market research shows that their suspense movies are viewed by an average of 3500 people, their comedies are viewed by 4500 people, and their dramas are viewed by 6000 people. The station buys a package of 100 movies, consisting of 15 suspense movies, 40 comedies, and 45 dramas. The movies will be shown two per week for 50 weeks. Find the expected number of viewers on a given movie.

I tried doing this but I am confusing myself.... I did 3 of these little probability things kind of like this earlier and I only got 1 out 3 right. So if you don't mind can you explain to me how to do this... I hate not getting things right the first time... Please help
Click here to see answer by stanbon(57219)

Question 204297: The bank officer rates applicants for credit. Ratings are normally distributed. The mean is 240 and the standard deviation is 60. If 36 applicants are randomly chosen, what is the probability that they will have a rating between 230 and 260?

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Question 204396: License paltes in a certain state have three letters followed by threee digits. How many different plates are possible if no repititions of letters or numbers are allowed?
Click here to see answer by checkley77(12569)

Question 204395: Carlin's Pizza House offers 3 kinds of salad, 15 kinds of pizza and 4 kinds of dessert. How many different three course meals can be ordered?
Click here to see answer by checkley77(12569)

Question 204394: Radio stations in the United States have call letters that begin with either K or W. Some ahve three letters; others have four letters. How many sets of three letter call letters are possible? How many sets of four letter call letters are possible?
Click here to see answer by checkley77(12569)

Question 204390: The telephone prefix for a university is 243. THe prefix is followed by four digits. How many telephones are pssible before a new prefix is needed?
Click here to see answer by checkley77(12569)

Question 204348: One card is selected at random from a standard 52-card deck of playing cards. Find the probability that the card selected is a jack.

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Question 204347: A card is selected from a deck of 52 playing cards. Find the probability of selecting
a) a seven given the card is a not a face card. (An ace is not a face card.)
b) a spade given the card is red.

Click here to see answer by checkley77(12569)

Question 204412: A bag contains 2 green, 9 brown, 7 yellow and 4 blue marbles. once a marble is selected, it is not replaced. find each probability.
1)p(brown, then yellow)
3)P(yellow, then yellow)
5 P(green, then not blue)
Click here to see answer by checkley77(12569)

Question 204428: In how many ways can the letters in the word SCRAMBLE be rearranged?
Click here to see answer by Alan3354(30959)

Question 204427: At a party, 28 handshakes took place. Each person shook hands exactly once with each of the others present. How many people were at the party.?
Click here to see answer by scott8148(6628)

Question 204434: The commissioner of MLB baseball would like to estimate the diameter of baseballs that are used in league play and now in the World Series. The manufacturer has specified that the baseballs are supposed to have a population mean diameter of 7.30 inches and a standard deviation equal to .04 inches. A random sample of 25 baseballs selected from a shipment indicates a sample average of 7.31 inches. Construct a 95% confidence interval estimate of the true average diameter of the baseballs in this shipment. Does the population of baseballs need to have a diameter that is normally distributed here?
Click here to see answer by stanbon(57219)

Question 204426: How many different 12-person juries can be selected from a pool of 24 people?
Click here to see answer by stanbon(57219)

Question 204435: According to the Center for Work-Life Policy, a survey of 500 highly educated women who left careers for family reasons found 66% wanted to return to work. Construct a 95% confidence interval for the proportion of highly educated women who left careers for family reasons and who want to return to work.
Click here to see answer by stanbon(57219)

Question 204453: Find these probabillities for a sample of 20 teenagers if 70% of them had compact disk players by the age of 16. Round to three decimal places, example 0.123.
a. At least 14 had CD players.
b. Exactly 9 had CD players.
c. More than 17 had CD players.
Click here to see answer by stanbon(57219)

Question 204466: At an annual flower show, 7 different entries are to be arranged in a row.
a) How many different arrangements of the entries are possible?
b) If the owners of the 1st, 2nd, and 3rd place entries will be awarded prizes of $100, $50, and $25 respectively, how many ways can the prizes be awarded?
Ok I am stuck again I really need help.. I hate word problems like this..
Click here to see answer by stanbon(57219)

Question 204463: In how many ways can 6 instructors be assigned to six sections of a course in mathematics?
I can not do word problems can you please explain this to me... I really need help...
Click here to see answer by jim_thompson5910(28476)

Question 204468: Swimming - The coach randommly selects 3 swimmers from a team of 8 to swim in a heat. What is the probability that she chose the 3 strongest swimmers.
Click here to see answer by stanbon(57219)

Question 204461: You have two bags. In each bag you have five balls labeled 1-5. If you randomly pick a ball from each bag, what is the probability that the balls picked will be the sum of nine?
Click here to see answer by jim_thompson5910(28476)

Question 204485: In the game of corn-toss, players throw corn-filled bags at a hole in a wooden platform. If a bag that hits the platform can hit any location with an equal likelihood find the probability that a tossed bag lands in the hole.
the hole is 6in in diameter.
the platform is 4ft by 2ft
Click here to see answer by stanbon(57219)

Question 204481: Six people are selected at random. What is the probability that none of the people in this group were born in the same month?
(I need to know how to set this up. thanks!)
Click here to see answer by Edwin McCravy(8880)

Question 204459: Does lovastatin (a cholesterol-lowering drug) reduce the risk of heart attack? In a Texas study,
researchers gave lovastatin to 2,325 people and an inactive substitute to 2,081 people (average age
58). After 5 years, 57 of the lovastatin group had suffered a heart attack, compared with 97 for the
inactive pill. (a) State the appropriate hypotheses. (b) Obtain a test statistic and p-value. Interpret
the results at α = .01. (c) Is normality assured? (d) Is the difference large enough to be important?
(e) What else would medical researchers need to know before prescribing this drug widely? (Data
are from Science News 153 [May 30, 1998], p. 343.)

Click here to see answer by stanbon(57219)

Question 204452: In a Gallup Survey, 90% of the people interviewed were unaware that maintaining a healthy weight could reduce the risk of stroke. If 15 people are selected at random, find the probability that at least 9 are unaware that maintaining a proper weight could reduce the risk of stroke.
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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