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1. The reaction times for a random sample of 8 persons to a stimulant were recorded as:3 4 3.1 5 2.9 2.3 3 4.1 Find a 90%
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   2. 25 views
2. A random sample of 144 patients at a local clinic who had cataracts removed during the past year showed an average age of 60
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   2. 34 views
3. A tyre manufacturer found that the sample mean tread life of 49 radial tyres tested was 52345 km with standard deviation 12943
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   2. 30 views
4. researcher wants to find the mean diameter of the washers produced in a company and takes 120 washers as a sample size. The
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5. Out of 100 students sampled, 70 of them said that they hoped to get married someday. With 99.7% confidence, what is the
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6. Assume that a sample is used to estimate a population mean μ. Use the given confidence level and sample data to find the margin
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7. Assuming CLT applies for the sample data given by 54, 56, 59, 59, 65, 66, 67, 68, 69, 76, 84, 86, 89, 94, 101 Find a 90% CI to
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8. Assuming CLT applies for the sample data given by 54, 56, 59, 59, 65, 66, 67, 68, 69, 76, 84, 86, 89, 94, 101 Find a 90% CI to
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9. Assuming CLT applies for the sample data given by 54, 56, 59, 59, 65, 66, 67, 68, 69, 76, 84, 86, 89, 94, 101 Find a 90% CI to
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   2. 55 views
10. A sample statistic, and margin of error are given. Find the corfidence interval likely to contain the population parameter of
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    2. 65 views
11. You intend to estimate a population mean with a confidence interval. You believe the population to have a normal distribution.
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    2. 103 views
12. A student was asked to find a 95% confidence interval for widget width using data from a random sample of size n = 18. Which of
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    2. 80 views
13. You measure 30 turtles' weights, and find they have a mean weight of 76 ounces. Assume the population standard deviation is 14.7
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    2. 75 views
14. You intend to estimate a population proportion with a confidence interval. The data suggests that the normal distribution is a
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    2. 76 views
15. A sample of 6 adult elephants had an average weight of 12,200 pounds, with a sample standard deviation of 200 pounds. We know
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    2. 97 views
16. A recent study of 25 students showed that they spend an average of $18.53 for gas per week. The sample standard deviation was
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    2. 66 views
17. Which type of confidence interval should you use in this situation? An economics professor randomly selected 100 millionaires in
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    2. 62 views
18. Suppose that, based on a simple random sample of n = 100 American adult men, we wish to calculate a 98% confidence interval for
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    2. 103 views
19. A simple random sample of size n is drawn from a population that is normally distributed. The sample​ mean, x​, is found to
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    2. 115 views
20. A sample statistic and margin of error are given. Find the confidence interval likely to contain the population parameter of
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    2. 81 views
21. Fifty two of a test panel of 175 consumers say that they would buy cereal A if it is presented on the market and 35 of another
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    2. 88 views
22. Sample of 15 test-tubes tested for number of times they cracked gave the sample mean of 1230 with a standard deviation of 270.
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    2. 67 views
23. In a random sample 500 people eating lunch at a cafeteria on various Fridays, it was found that 160 preferred seafood. Find 99%
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    2. 113 views
24. A ramdom sample of 150 workers showed that 90 workers are satisfied with the new medical scheme. Find a 90% confidence interval
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    2. 81 views
25. A ramdom sample of 150 workers showed that 90 workers are satisfied with the new medical scheme. Find a 90% confidence interval
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    2. 94 views
26. A recent survey of 81 customers who frequently visit convenient stores in Kimberly found that the mean value of purchases was R
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    2. 86 views
27. Light bulbs supplied by a certain company have a length life that is approximately normally distributed, with the standard
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    2. 96 views
28. . A lightbulb manufacturer wants to make sure the lightbulbs being produced give o the correct level ofbrightness. Brightness is
    1. 1 answer
    2. asked by Jeon
    3. 123 views
29. 4. Construct a 90% confidence interval for the sample mean based on the following data: x̄=145,n90=,σ=3.8
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    2. asked by Jeon
    3. 99 views
30. 4. Construct a 90% confidence interval for the sample mean based on the following data x̄ =145,n=90,o=3.8
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    2. asked by Jeon
    3. 143 views
31. If the sample size is 13 what condition must be satisfied to compute the confidence interval?
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    2. asked by Wanda
    3. 152 views
32. 1.Leana is interested in the proportion of people who live in her area who own a dog. She randomly selects 50 addresses within a
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    2. asked by Sweet pea
    3. 311 views
33. The confidence interval for a population mean has a margin of error of .075 determine the length of the confidence interval
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    2. asked by Genesis
    3. 234 views
34. In a 95% confidence interval approximately how many intervals would you expect to contain the population proportion and how many
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    2. asked by anonymous
    3. 566 views
35. Suppose that a random sample of five observations was taken from a normal population whosevariance is 25. The results are 8, 15,
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    2. asked by jhon kells
    3. 408 views
36. In a 95% Confidence Interval, the true mean has what chance of falling between the LowerLimit and Upper Limits of the calculated
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    2. asked by mona
    3. 788 views
37. A large health care system gave all nurses a flat wage increase. A union representative sampled 50 nurses and found that the
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    2. asked by Daniel
    3. 682 views
38. A large health care system gave all nurses a flat wage increase. A union representative sampled 50 nurses and found that the
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    2. asked by greg
    3. 2,172 views
39. Confidence interval interpretationEvery day, I try to estimate an unknown parameter using a fresh data set. I look at the data
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    2. asked by Skyfall
    3. 960 views
40. From time to time a manufacturer of pre-packed furniture needs to check the mean distance between pairs of holes drilled by a
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    2. asked by Help me plz
    3. 745 views
41. In a study designed to test the effectiveness of magnets for treating back​ pain, 35 patients were given a treatment with
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    2. asked by Kyra
    3. 727 views
42. The following data gives the amount of time (in minutes), it took a sample of 16 patients with hypertension to achieve their
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    2. asked by Jen
    3. 506 views
43. 5. A random sample of size 81 has sample mean 20 and sample standard deviation 3.(a) Is it appropriate to use a Student’s t
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    2. asked by Anonymous
    3. 1,294 views
44. The human resources department of a consulting firm gives a standard creativity test to a randomly selected group of new hires
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    2. asked by Ruth
    3. 808 views
45. A random sample of 50 four-year-olds attending day care centers provided a yearly tuition average of 3987, with a population
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    2. asked by Kyle
    3. 739 views
46. Direct mail advertisers send solicitations​ ("junk mail") to thousands of potential customers in the hope that some will buy
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    2. asked by Anonymous
    3. 1,024 views
47. The Maximum Error of Estimate is exactly equal to half of the width of the confidence interval. T-F, and why or why not?
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    2. asked by sharon
    3. 637 views
48. In a study of the relationship between pet ownership and physical activity in older adults, 575 subjects reported that they
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    2. asked by YOMO
    3. 574 views
49. In 2015, the average price of new homes in a certain suburb was $145,000. Assume that thismean is based on a random sample of
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    2. asked by Jerold
    3. 617 views
50. Suppose you are told that a 95% confidence interval for the average price of a gallon of regular gasoline in your state is from
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    2. asked by Alice
    3. 627 views
51. Salaries of 50 college graduates who took a statistics course in college have a​ mean, x of $68,200. Assuming a standard​
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    2. asked by casey
    3. 1,288 views
52. B) A random sample of 16 mid-sized cars tested for fuel consumption gave a mean of 26.4Kilometers per liter with a standard
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    2. asked by joe
    3. 711 views
53. Table 9: Visitor NumbersTotal visitors: 2004. 2005. 2006 3,135,727. 3,164,906. 3,281,435 Total visitor days: 2004. 2005. 2006
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    2. asked by Candice
    3. 650 views
54. (a) An insurance company wants to estimate the proportion of people unsatisfied with their new telephone help service. A survey
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    2. asked by Laurence
    3. 456 views
55. A manufacturing company wishes to estimate the number of items that its workforce can produce on average each hour now that they
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    2. asked by Sam
    3. 528 views
56. A car manufacturing company is interested in finding the average fuel consumption of one of its new models Leopard F-type.
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    2. asked by Anonymous
    3. 516 views
57. Sample size= 16 mean=3.48 and standard deviation=0.92. For a 99% confidence interval, what is the Margin Of Error
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    2. asked by Knight
    3. 566 views
58. Forty-nine items are randomly selected from a population of 500 items. The sample mean is 40 and the sample standard deviation
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    2. asked by Albert
    3. 924 views
59. For 30 randomly selected Rolling Stones concerts, the mean gross earnings is 2.37 million dollars. Assuming a population
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    2. asked by Lala
    3. 667 views
60. What is a 95% confidence interval for the time my colleagues can stay awake on average for all of my colleaguesWhat is a 95%
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    2. asked by kish
    3. 568 views
61. The manager of Lone Star Restaurant believes that the average wait time of the Saturday evening meal is 30 minutes. To test this
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    2. asked by Lucy
    3. 663 views
62. A survey of 925 voters in one state reveals that 408 favor approval of an issue before the legislature. Construct the 90%
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    2. asked by Lizzy
    3. 557 views
63. The Wall Street Journal reported that automobile crashes cost the United States $162 billion annually (The Wall Street Journal,
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    2. asked by SV
    3. 1,056 views
64. In a random sample of 63 women at a company, the mean salary is $48,902 with a standard deviation of $5270. In a random sample
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    2. asked by sweet12
    3. 706 views
65. In a random sample of 63 women at a company, the mean salary is $48,902 with a standard deviation of $5270. In a random sample
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    2. asked by sweet12
    3. 845 views
66. In a sample of 200 people, 154 said they watched educational television. Find the 90% confidence interval of the true proportion
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    2. asked by Ale
    3. 1,236 views
67. A savings and loan association needs information concerning the checking account balances of its local customers. A random
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    2. asked by Giselle
    3. 963 views
68. FORMAT INSTRUCTIONSEach question requires the use of MINITAB to solve. Please submit your work as a WORD or similar document.
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    2. asked by Amer
    3. 557 views
69. The U.S. Geological Survey compiled historical data about Old Faithful Geyser (Yellowstone National Park) from 1870 to 1987. Let
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    2. asked by Interval Estimate
    3. 902 views
70. To help consumers assess the risks they are taking, the Food and Drug Administration (FDA) publishes the amount of nicotine
    1. 3 answers
    2. asked by Z
    3. 2,321 views
71. An online site presented this question, 'Would the recent norovirus outbreak deter you from taking a cruise?' Among 34,327
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    2. asked by slomomo
    3. 805 views
72. In the week before and the week after a holiday, there were 12,000 total deaths, and 5916 of them occurred in the week before
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    2. asked by slomomo
    3. 857 views
73. In a sample of seven cars, each car was tested for nitrogen-oxide emissions (in grams per mile) and the following results were
    1. 1 answer
    2. asked by slomomo
    3. 1,621 views
74. Determine the level of the confidence given the confidence coefficient z(α/2) for the following situation: z(α/2) = 1.96
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    2. asked by slomomo
    3. 1,744 views
75. Suppose we would like to estimate the mean amount of money spent on books by students in the fall semester. We have the
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    2. asked by Elena
    3. 1,505 views
76. 7. Give and interpret the 95% confidence interval for the hours of sleep a student gets.
    1. 1 answer
    2. asked by Anonymous
    3. 608 views
77. Produce a 99.9 % confidence interval for the population mean body temperature of a healthy male. Then do the same for the
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    2. asked by j
    3. 521 views
78. A filing machine designed to fill soda bottles with 16 ouncesof soda. The distribution for the weight of the bottles is normal.
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    2. asked by Leslie Meagan
    3. 759 views
79. There are 300 students enrolled in Business Statics . Historically,exam scores are normally distributedwith a standard deviation
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    2. asked by Leslie Meagan
    3. 588 views
80. interested in the mean IQ score of a given group of children. It is known that the IQ scores of the group have a standard
    1. 2 answers
    2. asked by Anonymous
    3. 676 views
81. The following data represent the asking price of a simple random sample of homes for sale. Construct a 99% confidence interval
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    2. asked by LADO
    3. 1,669 views
82. A nutritionist wants to determine how much time nationally people spend eating and drinking. Suppose for a random sample of 1065
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    2. asked by LADO
    3. 2,612 views
83. An agricultural researcher is interested in estimating the mean length of the growing season in a region. Treating the last 10
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    2. asked by STATS 2
    3. 1,931 views
84. b. A mobile company XYZ wants to conduct a survey to find the proportion P of those customers that are happy with the purchase
    1. 0 answers
    2. asked by aima
    3. 587 views
85. Thank you in advance for anyone able to help me with this...In a sample of 67 randomly selected students, 27 favored the amount
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    2. asked by linda
    3. 422 views
86. I would really appreciate help with this.In a survey of 1000 large corporations, 252 said that, given a choice between a job
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    2. asked by Mandy
    3. 758 views
87. Workers in several industries were surveyed to determine the proportion of workers who feel their industry is understaffed. In
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    2. asked by tia
    3. 1,274 views
88. A random sample of 16 mid-sized cars tested for fuel consumption gave a mean of 26.4 kilometers per litre with a standard
    1. 2 answers
    2. asked by John
    3. 729 views
89. 1. A confidence interval can be calculated to estimate the population mean when the population is normally distributed or the
    1. 1 answer
    2. asked by morgana
    3. 726 views
90. A sample of 40 CDs from a student's collection showed a mean length of 52.74 minutes with a standard deviation of 13.21 minutes.
    1. 1 answer
    2. asked by Anonymous
    3. 797 views
91. A bank wishing to determine the average amount of time a customer must wait to be served took a random sample of 100 customers
    1. 2 answers
    2. asked by Anonymous
    3. 1,055 views
92. In a study of 200 students, 42 were found to have a GPA greater than 3.0. Find a98% confidence interval estimate of the
    1. 1 answer
    2. asked by Jason
    3. 582 views
93. Annual starting salaries for college graduates with degrees in business administration are generally expected to be between
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    2. asked by Vanessa
    3. 720 views
94. Recently, a university surveyed recent graduates of the English Department for their starting salaries. Four hundred graduates
    1. 2 answers
    2. asked by Ray
    3. 1,175 views
95. Find the 95 percent range for the sample mean, assuming that each sample is from a normalpopulation. a. ì = 200, ó = 12, n =
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    2. asked by Kevin
    3. 439 views
96. Professor York randomly surveyed 240 students at Oxnard University, and found that 150 of the students surveyed watch more than
    1. 3 answers
    2. asked by Angela
    3. 2,277 views
97. You have an SRS of 15 observations from a Normally distributed population. What critical value would you use to obtain a 98%
    1. 1 answer
    2. asked by UCI STUDENT
    3. 1,878 views
98. Construct a 95% confidence interval for the population mean. 5. Airfare A random sample of airfare prices (in dollars) for a
    1. 1 answer
    2. asked by anna
    3. 594 views
99. A clinical trial tests a method designed to increase the probability of conceiving a girl. In the study 624 babies were born,
    1. 0 answers
    2. asked by Stephanie
    3. 971 views
100. A student union wants to obtain a 90% confidence interval for the proportion of “full time” students who hold a part-time
     1. 1 answer
     2. asked by Steven
     3. 459 views