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    Hypothesis Testing, Confidence Interval & Probability

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    4. Using the data below, make a histogram, box plot, compute the mean, median, mode and standard deviation
    City and State Crime
    Albuquerque, NM 8515
    Anaheim, CA 2827
    Anchorage, AK 4370
    Arlington, TX 5615
    Atlanta, GA 10759
    Aurora, CO 5079
    Austin, TX 6406
    Birmingham, AL 7030
    Boston, MA 4986
    Buffalo, NY 5791
    Charlotte, NC 7484
    Chicago, IL 6333
    Cincinnati, OH 5694
    Cleveland, OH 5528
    Colorado Springs, CO 4665
    Columbus, OH 8247
    Corpus Christi, TX 6266
    Dallas, TX 8201
    Denver, CO 4685
    Detroit, MI 8163
    El Paso, TX 5106
    Fort Worth, TX 6636
    Fresno, CA 6145
    Honolulu, HI 4671
    Houston., TX 6084
    Indianapolis, IN 4306
    Jacksonville, FL 6118
    Kansas City, MO 9882
    Las Vegas, NV 4520
    Lexington, KY 5315
    Long Beach, CA 3407
    Los Angeles, CA 3306
    Louisville, KY 5102
    Memphis, TN 6958
    Mesa, AZ 5590
    Miami, FL 8619
    Milwaukee, WI 6886
    Minneapolis, MN 7247
    Nashville, TN 7276
    New Orleans, LA 6404
    New York, NY 2968
    Newark, NJ 6068
    Oakland, CA 6820
    Oklahoma City, OK 8464
    Omaha, NE 5809
    Philadelphia, PA 5687
    Phoenix, AZ 6888
    Pittsburgh, PA 5246
    Portland, OR 6897
    Raleigh, NC 6327
    Riverside, CA 3610
    Sacramento, CA 5859
    San Antonio, TX 6232
    San Diego, CA 3405
    San Francisco, CA 4859
    San Jose, CA 2363
    Santa Ana, CA 3008
    Seattle, WA 8397
    St. Louis, MO 11765
    St. Paul, MN 6215
    Stockton, CA 5638
    Tampa, FL 8675
    Toledo, OH 6721
    Tucson, AZ 8079
    Tulsa, OK 6234
    Virginia Beach, VA 3438
    Washington, DC 6434
    Wichita, KS 5733

    5. In child custody case, about 70% of the fathers win the case is they contest it. IN the next thee custody cases what is the probability that all three win

    6. SOB's systolic blood pressure is a random variable with a mean of 145 mmHG and a standard deviation of 20mmHG. If the SOB's blood pressure is taken at a randomly chosen moment what is the probability it will be below 135? What is the probability it will be over 175?

    7. Find the required sample size to estimate the mean starting salary for a new CEO with a 95% confidence, assuming the standard deviation is $7,500 with an error of $2,000. Assume the population N is 1,250,000.

    8. 95% of Popcorn kernels take between 100 and 200 seconds to pop. What sample size (number of kernels) would be needed to estimate the true mean seconds to pop with and error of 5 seconds and 95% confidence level?

    9. A sample of 20 pages was taken from the 2,000 page phone directory. On each page, the mean area devoted to display ads was shown - see data below. Construct a 95% confidence interval for the true mean
    Display Ads
    0
    260
    356
    403
    536
    0
    268
    369
    428
    536
    130
    268
    396
    469
    536
    162
    338
    403
    536
    536

    10. Stores are not supposed to sell cigarettes to teenagers. Of 320 stores checked, 82 stores sold cigarettes to teens. Is the goal being achieved is to reduce the % of stores selling cigarettes to under 20%. (1) Do a hypothesis test to reject or fail to reject the Ho and (2) construct a 95% confidence interval to determine the true percent of stores who allow teens to purchase cigarettes.

    11. The mean number of arrivals at Chicago O'Hare is 195 flights per hour. The historical standard deviation of flight arrivals at O'Hare is 13. Using the data below, set up a hypothesis test to see if there has been an increase in arrivals. Would you arrive at a different decision if Alpha were .01?
    Flights
    210
    215
    200
    189
    200
    213
    202
    181
    197
    199
    193
    209
    215
    192
    179
    196
    225
    199
    196
    210
    199
    188
    174
    176
    202
    195
    195
    208
    222
    221

    12. One group of accounting students took an online course, The second groups of students took the same accounting course in a traditional classroom. At Alpha of .10 is there any difference in the results. Find p-value and interpret it
    Online Students Classroom
    Mean 9.1 10.3
    Sample Std.dev. 2.4 2.5
    N count 20 20

    13. In a lottery each digit is supposed to have the same probability of occurrence. The table below shows the occurrence of each digit of 89 consecutive daily drawings. The Research questions is: at the .01 Alpha can you reject the Ho that the digits are from a uniform population.
    Digit Frequency
    0 39
    1 27
    2 35
    3 39
    4 35
    5 35
    6 27
    7 42
    8 36
    9 41
    Total 356

    14. A sample of 100 mortgages approved during the course of a year showed that 31 were issued to single-earner family or individual. The historical average is 25%. Has the percentage of single-earned or individual mortgages risen? Test using Alpha .05.

    See attached file.

    © BrainMass Inc. brainmass.com October 10, 2019, 1:14 am ad1c9bdddf
    https://brainmass.com/statistics/confidence-interval/hypothesis-testing-confidence-interval-probability-326838

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    Solution Summary

    The solution provides step by step method for the calculation of testing of hypothesis, sample size, confidence interval, normal probability and descriptive statistics. Formula for the calculation and Interpretations of the results are also included. Interactive excel sheet is included. The user can edit the inputs and obtain the complete results for a new set of data.

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