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    Confidence Interval

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    Confidence Levels and the Width of Confidence Intervals

    Suppose that a random sample of 50 bottles of a particular brand of cough syrup is selected, and the alcohol content of each bottle is determined. Let mu denote the average alcohol content for the population of all bottles of the brand under study. Suppose that the resulting 95% confidence interval is (7.8, 9.4). Would a 90%

    True Population Mean of High School Attendance

    See the attached file. Vito has completed the analysis of some sample data from a recent survey of local high school students. He has determined that his sample has attended an average of 145 days of school this year, with a standard error of the average of 8 days. The sample was random and fairly large. (refer to document atta

    Sample Size: Calculate Accuracy

    Having been retained by the National Native American Political Party to conduct a poll of residents of Muscogee, Oklahoma, you have worked diligently on completing interviews with residents of that town for three weeks. Your budget of $10,000 is expended. You have completed 270 interviews. (A) If you promised to deliver a su

    Confidence Intervals

    Decoders often use the fact that the letter "e" appears in written work more than any other letter. Make a photocopy of an article in a newspaper or magazine {see article below}. Choose two different paragraphs from that article/page (must be a minimum of 25 words in each paragraph and the paragraphs must contain the letters e a

    Confidence Intervals Estimators

    Suppose an SRS of 25,000 Americans were surveyed and 16,000 of them said they have blue colored eyes. a) Create a 98% confidence interval estimator for the population proportion of Americans that have blue colored eyes. b) What is the minimum sample size that would be required to estimate the population's proportion to wi

    Confidence Intervals, Sample Size

    In order to determine the fuel efficiency for the Subaru Impreza the following information was gathered: a) A random sample of 12 Imprezas were driven yielding the following miles per gallon (mpg). 25.1 24.6 22.5 27.8 26.1 21.0 23.9 28.4 24.4 23.5 26.2 20.7 Create a 95% confidence interval estimate

    Confidence Intervals for Adirondack Areas

    To estimate the mean size of maple trees in a certain area of the Adirondacks. A sample of 15 maple tree heights is collected (refer to the data set). Data Sheet numbers: 50, 41, 31, 33, 47, 39, 41, 44, 39, 32, 35, 43, 37, 49, 51 a) Determine a 90% confidence interval for the population mean of maple tree heights.

    Confidence Intervals

    8.20 425 510 629 236 654 200 276 501 811 332 424 674 676 694 710 662 633 a. Find a 90% confidence interval for the mean number of tongue flicks per 20 minutes for all juvenile common lizards. Assume a population standard deviation of 190.0 (note: The sum of the data is 9047.) b. interpret your answer from part (a)

    Normal Distribution, Mean and Standard Deviation

    7.40 A variable of a population has a mean of m = 35 and a standard deviation of o = 42. a. If the variable is normally distributed, identify the sampling distribution of the sample for samples of 9. b. Can you answer part (a) if the distribution of the variable under consideration is unknown? Explain your answer. c. C

    Test of hypothesis, Confidence Interval

    1) Recruit 25 volunteers who have received a medication and find they have a mean concentration of 7 with a standard deviation of 2. Assume normally distributed. FIND: 95% CONFIDENCE INTERVAL for pop mean concentration Find: 99% confidence interval for pop var of conc HOW large a sample is needed to ensure the length of th

    Determine the Confidence Intervals

    In the atmosphere, the ratio of toxic gas, for a given volume of air, is a normally distributed random variable with mean μ and variance Σ² which are unknown. We take n samples, whose values are X1, X2,..., Xn. Please see attachment for questions 1, 2, and 3.

    Confidence Intervals, Samples, and Unknown Variance

    Let (X1, X2,..., Xn) be a sample, where each Xi is a random variable of normal distribution with mean mu and variance sigma². Let us suppose that n = 20, and sigma² = 9. An experiment has yielded the results (X1, X2,..., X20), and we have calculated that the empirical mean x20 = 2.09. 1) Give a confidence interval with leve

    Probability Confidence Intervals

    I am currently studying probability and am having a bit of trouble with the following questions. Can you help me? If you can, thank you very much. The questions are: 1.) An office manager wishes to estimate the mean time required to handle customer complaints. A sample of 38 complaints shows a mean time of 28.7 minutes with a

    Test of Hypothesis: Confidence Interval Example

    The data in the table below (you may assume these to be normally distributed) give the iron intakes, in milligrams, in a 24 hour period for 45 randomly selected adult females under the age of 51. 15.0 18.1 14.4 14.6 10.9 18.1 18.2 18.3 15.0 16.0 12.6 16.6 20.7 19.8 11.6 12.8 15.6 11.0 15.3 9.4 19.5 18.3 14.5 16.6 11.5 16.

    Confidence interval for the true population proportion

    A citizen's group is interested in the portion of the population that opposes the expansion at O'Hare airport. In a survey of 1,440 randomly selected people, 1098 people opposed the expansion. Construct a 95% confidence interval for the true population proportion.

    Construct confidence interval

    A study of 64 convicted felons was conducted regarding the age of the first offense. The mean age of first offense was 13.2 years with a s.d. of 4.6 years. Construct a 94% confidence interval for the mean age of the first offense for all convicted felons and graph.

    GMAT Scores Coordinated

    Please use excel when necessary: 1)The GMAT scores of MBA candidates are normally distributed with a mean of 568 and Standard eviation of 25.6 What is the probabilitie of candidates scoring higher than 600 ? 2) A financial Manager is interested to study DM students. A random sample of 256 students salaries totaled $ 9,067,

    Determining Confidence Coefficients

    Olive Garden Swiss Chalet Sample size 50 45 Sample mean $22 $18 Standard deviation $3.00 $3.25 How do I create interval estimate for the difference between the average fees of the 2 restaurants at a confidence co-effiecent at 95 % What do I need to do to find o

    Confidence Intervals Estimated

    It is desired to estimate which of the two soft drinks, Coke or Pepsi, UCLA students prefer. A random sample of 167 UCLA students produced the following 95% confidence interval for the proportion of UCLA students who perfer Pepsi: (.344, .494) A. Is this a large enough sample for this analysis to work? aa) Yes, since N=167, whic

    Confidence interval (Multi Choice)

    Currently the stock market is declining. A stock broker wishes to determine his portfolio. She randomly choose 64 daily stock prices for stock A from the past year data, and obtain the 95.44% confidence interval for the average price to be [ $30.0 , $40.0] A. What is the confidence coefficient? aa) 50% bb) .9544 cc) 40.00 dd) $3

    Statas

    What is the predicted value for x = 10, if the regression equation is: y' = 106.8 - 3.1x? If alpha/2 = 0.02, the confidence interval is the ______% confidence interval. The Academy of Orthopedic Surgeons states that 80 out of every 100 women wear shoes that are too small for their feet. A researcher wants to be 98% c

    Statistical Research Problem

    Note: Moved from STATS to MATH because more OTAs available in the latter category. NOTE: I DO NOT WANT ANYONE TO WRITE MY PAPER I JUST NEED 5-6 TECHNIQUES TO INCLUDE IN MY PAPER and I'm unsure which ones are best to use: Here is the outline listing what I need to include as well as the first page of my proposal summary a

    95% Confidence Interval

    See Attached file in "Word". Please show all work and give a full detailed explanation of answer. Thank you. Find the 95% confidence interval for the average time spent waiting for a prescription to be filled at Rex's Rx Center if a random sample of 64 customers showed an average waiting time of 12.3 minutes with a standard

    Estimation:Confidence Interval for proportions

    A random sample of 90 prisoners in a large state prison revealed that 20% were college graduates. Find the 99% confidence interval in the population sampled for the percentage of prisoners who are college graduates.

    Confidence interval

    A music teacher asks six randomly selected students how many hours per week they practice their instrument. the teacher receives the following answers:10,12,8,9,16,5. Find a 90% confidence interval for the average length of time that a student pratices each week.

    Confidence Interval Descriptions

    Please see the attached file for full problem description. You are given a quantitative data set, which represent the wages of 80 tradesmen in the construction industry (as $/hr). Obtain a 95% confidence interval for the population mean wage , given the following information: • ; • .

    Confidence Interval Expected Values

    It has been determined that the correlation between a very good predictor variable and college GPA is .69. Also, the standard error of the estimate is .54 based on the four point grading scale. If a student should expect a 2.75 GPA, what are the 95% expectations for the student?