MA116A Elements of Statistics Exam 1 by Daeshik Park – Student’s Name: Student’s Score: /100 Directions: You must show your work in every detail and use complete sentences to describe your answers; otherwise you will get heavy penalty. Write neatly your work for each problem by circling your answers if possible. No calculator features if not indicated. Round all numbers to two decimal places if needed. 1. [6 points] Classify and circle the aspect of statistics for each statement. a) From past figures, it is predicted that 47% of the registered voters in Virginia will vote in the June primary. Circle your answer: Design, Description or Inference. b) The average age of the students in a statistics is 25 years. Circle your answer: Design, Description or Inference. 2. [3 points] To estimate the percentage of defective a machine is producing, a quality control analyst inspects the first 100 items produced in a day. Does this technique produce a random sample? 3. [6 points] Determine whether the summary measure is better described as a parameter or a statistic. a) The average GPA of a university's graduating class. Circle your answer: Parameter or Statistic. b) The proportion of teenagers in a nationwide survey who stated that they consumed alcohol on a regular basis. Circle your answer: Parameter or Statistic. 4. [6 points] The following table shows the heights of the five tallest mountains in North America. McKinley 20,320 1 a) Is the variable Height discrete or continuous? Logan 19,850 2 Citlaltepec 18,700 3 St. Elias 18,008 4 b) Is the variable Rank discrete or continuous? Popocatepetl 17,930 5 5. The following data provide the daily protein intake (in grams of protein per kilogram of body weight) for 14 competitive athletes. 3.5 2.2 2.7 1.7 2.3 1.5 2.8 1.8 2.0 2.0 1.9 1.7 1.8 1.6 a) [8 points] Find the mean and the median.
MA116A Elements of Statistics – Exam 1 by Daeshik Park Student’s Name: Student’s Score: /100 Directions: You must show your work in every detail and use complete sentences to describe your answers; otherwise you will get heavy penalty. Write neatly your work for each problem by circling your answers if possible. Round all numbers to two decimal places if needed. No calculator features if not indicated. 1. [6 points] Classify and circle the aspect of statistics for each statement. a) From past figures, it is predicted that 47% of the registered voters in Virginia will vote in the June primary. Circle your answer: Design, Description or Inference. b) The average age of the students in a statistics is 25 years. Circle your answer: Design, Description or Inference. 2. [3 points] To estimate the percentage of defective a machine is producing, a quality control analyst inspects the first 100 items produced in a day. Does this technique produce a random sample? 3. [6 points] Determine whether the summary measure is better described as a parameter or a statistic. a) The average GPA of a university's graduating class. Circle your answer: Parameter or Statistic. b) The proportion of teenagers in a nationwide survey who stated that they consumed alcohol on a regular basis. Circle your answer: Parameter or Statistic. 4. [6 points] The following table shows the heights of the five tallest mountains in North America. McKinley 20,320 1 Logan 19,850 2 Citlaltepec 18,700 3 St. Elias 18,008 4 Popocatepetl 17,930 5 a) Is the variable Height discrete or continuous? b) Is the variable Rank discrete or continuous? 5. The following data provide the daily protein intake (in grams of protein per kilogram of body weight) for 14 competitive athletes. 3.5 2.2 2.7 1.7 2.3 1.5 2.8 1.8 2.0 2.0 1.9 1.7 1.8 1.6 a) [8 points] Find the mean and the median.