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Newest Confidence Interval Questions

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%
   1. 1 answer
   2. 97 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. 99 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. 120 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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   2. 130 views
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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   2. 109 views
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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   2. 187 views
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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   2. 108 views
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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   2. 90 views
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. 120 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. 122 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. 168 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. 146 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. 134 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. 140 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. 170 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
    1. 1 answer
    2. 138 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. 126 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
    1. 5 answers
    2. 178 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
    1. 1 answer
    2. 203 views
20. A sample statistic and margin of error are given. Find the confidence interval likely to contain the population parameter of
    1. 1 answer
    2. 142 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. 153 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. 130 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. 181 views
24. A ramdom sample of 150 workers showed that 90 workers are satisfied with the new medical scheme. Find a 90% confidence interval
    1. 1 answer
    2. 158 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. 173 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. 151 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. 165 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. 195 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. 158 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. 231 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. 204 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. 392 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. 312 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. 635 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. 505 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. 865 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. 748 views
38. A large health care system gave all nurses a flat wage increase. A union representative sampled 50 nurses and found that the
    1. 4 answers
    2. asked by greg
    3. 2,254 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. 1,035 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. 822 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. 813 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. 582 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. 1,369 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. 886 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. 839 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. 1,115 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. 714 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. 648 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. 699 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. 697 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. 1,363 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. 788 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. 749 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. 521 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. 604 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. 595 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. 624 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. 997 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. 753 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%
    1. 1 answer
    2. asked by kish
    3. 632 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. 740 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. 634 views
63. The Wall Street Journal reported that automobile crashes cost the United States $162 billion annually (The Wall Street Journal,
    1. 1 answer
    2. asked by SV
    3. 1,138 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. 767 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
    1. 0 answers
    2. asked by sweet12
    3. 915 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. 1,310 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. 1,033 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. 632 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. 966 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. 2,406 views
71. An online site presented this question, 'Would the recent norovirus outbreak deter you from taking a cruise?' Among 34,327
    1. 0 answers
    2. asked by slomomo
    3. 865 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
    1. 0 answers
    2. asked by slomomo
    3. 931 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. 1,684 views
74. Determine the level of the confidence given the confidence coefficient z(α/2) for the following situation: z(α/2) = 1.96
    1. 1 answer
    2. asked by slomomo
    3. 1,823 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
    1. 1 answer
    2. asked by Elena
    3. 1,569 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. 670 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. 575 views
78. A filing machine designed to fill soda bottles with 16 ouncesof soda. The distribution for the weight of the bottles is normal.
    1. 1 answer
    2. asked by Leslie Meagan
    3. 835 views
79. There are 300 students enrolled in Business Statics . Historically,exam scores are normally distributedwith a standard deviation
    1. 1 answer
    2. asked by Leslie Meagan
    3. 660 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. 746 views
81. The following data represent the asking price of a simple random sample of homes for sale. Construct a 99% confidence interval
    1. 2 answers
    2. asked by LADO
    3. 1,755 views
82. A nutritionist wants to determine how much time nationally people spend eating and drinking. Suppose for a random sample of 1065
    1. 1 answer
    2. asked by LADO
    3. 2,686 views
83. An agricultural researcher is interested in estimating the mean length of the growing season in a region. Treating the last 10
    1. 1 answer
    2. asked by STATS 2
    3. 2,005 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. 671 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
    1. 0 answers
    2. asked by linda
    3. 486 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. 822 views
87. Workers in several industries were surveyed to determine the proportion of workers who feel their industry is understaffed. In
    1. 1 answer
    2. asked by tia
    3. 1,350 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. 808 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. 815 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. 871 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. 1,136 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. 644 views
93. Annual starting salaries for college graduates with degrees in business administration are generally expected to be between
    1. 0 answers
    2. asked by Vanessa
    3. 801 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. 1,256 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 =
    1. 1 answer
    2. asked by Kevin
    3. 505 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. 2,365 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. 1,960 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. 674 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. 1,055 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. 524 views