Skip to content
Solved Assignments

MATH302 Statistics�Final Examination

Final exam for statistics.

Preview 4 of 10 pages

See the first 4 pages exactly as they appear in the document.

  1. Page 1
    Read page 1 as text

    Statistics — M ATH302 Final Examination INSTRUCTIONS : This is an open - book and open note examination. You may use your textbook, notes, your computer and a calculator during the examination. However, you are not to consult — in any manner -- with anyone while you complete this examination. Absolutely no collaboration is permitted on this examination. This examination consists of this cover sheet and 7 consecutively numbered pages. There are 25 questions. Each question on this exam has the same weight — f our point s — and this examination will count as 2 0% of your final grade for the course. AFTER you have answered all of the questions posed in this examination, you are to upload your answers into the Final Exam Shell in the Exam s section of our online course. DO NOT access the Final Exam Shell until AFTER you have formulated your answers to all of the questions on this examination. Remember, y ou will be able to access the Final Exam Shell only once. You must en ter your answers into the Final Exam Shell in the Exam s section of our course by 1 1:59 PM Eastern Time on the due date noted in the course calendar and in the Announcements section of our online c lassroom . No late submissions will be accepted.

  2. Page 2
  3. Page 3
    Read page 3 as text

    1 1 . A lawyer researched the average number of years served by 45 different justices on the Supreme Court. The average number of years served was 13.8 years with a standard deviation of 7.3 years. What is the 95% confidence interval estimate for the average number of years served by all Supreme Court justices? Place your limits , rounded to 1 decimal place , in the blanks. When entering your answer into the Final Exam Shell do not use any labels or symbols. Simply provide the numerical values. For example, 1 2.3 would be a legitimate entry. Lower limit (first blank) = _____ 11.7 ___, Uppe r limit (second blank) = ___ 15.9 ____. 2 . Some defendants in criminal proceedings plead guilty and are sentenced without a trial, whereas others who plead innocent are subsequently found guilty and then are sentenced. In recent years, legal scholars have speculated as to whether sentences of those who plead guilty differ in severity from sentences for those who plead innocent and are subsequently judged guilty. Consider the data given below on defendants accused of robbery, all of whom, by the way, had previous prison records. At the .01 level of significance, d o these data suggest that the proportion of all defendants in these circumstances who plead guilty and are sent to prison differs from the proportion who are sent to prison after pleading innocent and being found guilty? Plea Guilty Not Guilty Number judged guilty n 1 = 191 n 2 = 64 Number sentenced to prison x 1 = 101 x 2 = 56 Sample proportion 1 ˆ = .529 p 2 ˆ = .875 p A. No, because the test value - 1.96 is inside the interval ( - 2.58, 2.58) B. No, because the test value - 4.94 is outside the interval ( - 1.96, 1.96) C. Yes, because the test value - 4.94 is outside the interval ( - 2.58, 2.58) D. Yes, because the test value 2.58 is inside the interval ( - 4.94, 4.94) Solution: C. Yes, because the test value - 4.94 is outside the interval ( - 2.58, 2.58) 3 . Serum ferritin is used in diagnosing iron deficiency. In a study conduct ed recently researchers discovered that in a sample of 28 elderly men the sample standard d eviation of serum ferritin was 52.6 mg/L. For 26 younger men the sample standard deviation was 84.2 mg/L. At the .01 level of significance, d o these data support the conclusion that the ferritin distribution in elderly men has a smaller variance than in younger men? A. No, because the test value 1.60 is less than the critical value of 2.54 B. Yes, because the test value 2.56 is greater than the critical value of 2.54 C. Yes, because the test value 0.390 is less than the critical value 2.54 D. Yes, because the test value 2.56 is greater than the critical value 0.394

  4. Page 4
    Read page 4 as text

    2 Solution: B. Yes, because the test value 2.56 is greater than the critical value of 2.54 4 . The data presented in the table below resulted from an experiment in which seeds of 5 different types were planted and the number of seeds that germinated within 5 weeks after planting was recorded for each seed type. At the .01 level of significance, is the proportion of seeds that germinate dependent on the seed type? Seed Type Observed Frequencies Germinated Failed to Germinate 1 31 7 2 57 33 3 87 60 4 52 44 5 10 19 A. Yes, because the test value 16.86 is greater than the critical value of 13.28 B. Yes, because the test value 16.86 is less than the critical value of 14.86 C. No, because the test value 16.86 is greater than the critical value of 13.28 D. No, because the test value 13.28 is less than the critical value of 16.86 Solution: A. Yes, because the test value 16.86 is greater than the critical value of 13.28 5. A manufacturer of flashlight batteries took a sample of 13 batteries from a day’s production and used them continuously until they failed to work. The life lengths of the batteries , in hours , until they failed were : 342, 426, 317, 545, 264, 451, 1049, 631, 512, 266, 492, 562, and 298. These data are also available in the worksheet Batteries in the Excel workbook M ATH302 _Final.xls. At the .05 level of significance, is there evidence to suggest that the mean life length of the batteries produced by this manufacturer is more than 400 hours? A. No, because the p - value for this test is equal to .1164 B. Yes, because the test value 1.257 is less than the critical value 1.782 C. No, because the test value 1.257 is greater than the critical value 1.115 D. Yes, because the test value 1.257 is less than the critical value 2.179 Solution: A. No, because the p - value for this test is equal to .1164 6. A survey of 85 families showed that 36 owned at least one DVD player. Find the 99% confidence interval estimate of the true proportion of families who own at least on DVD player. Place your limits, rounded to 3 decimal place s , in the blanks. When entering your answer into the Final Exam Shell do not use any labels or symbols other than the decimal point. Simply provide the numerical values. For example, 0.1 23 would be a legitimate entry. Lower limit (first blank) = __ 0.285 ________, Upper limit (second blank) = ____ 0.562 _____.

6 more pages in the full document

Unlock it once and it stays in your library, ready to chat with or turn into flashcards.

Unlock the full document

More Statistics study materials

See all

Study this document with CramX

Once it is in your library, every tool can work from it.