NAME_____Princess Sebo_________________________________________ MAT130 Descriptive Statistics Review Homework Identify whether the data is quantitative or qualitative and identify the variable: (1) The average miles per gallon of all new cars. Quantitave data (2) The nitrogen concentration (milligrams of nitrogen per liter of water) in Lake Winnepesaukee. Quantitative data (3) The cell phone number of each SNHU student. Qualtitave data (4) Your nation of origin. Qualitative data Identify whether the quantitative data is continuous or discrete: (5) Measure the time it takes a student selected at random to register for the fall term. Continuous (6) Count the number of bad checks drawn on a selected bank on a selected day at random. discrete (7) Measure the amount of gasoline needed to drive your car 200 miles. continuous (8) Points scored in a SNHU soccer game. discrete Determine whether the underlined value is a statistic or parameter. (9) In a study of all 1,398 male students at a college, 17% say they own an X-box. parameter (10) In a poll of a sample of 5,000 adults in New Hampshire, 65% say they own an American car. Statistic (11) The following histograms depict two frequency distributions. Which histogram has the larger standard deviation? Explain Why. 3.5 4.5 4 3.5 3 2.5 Frequency 2 1.5 1 0.5 0 3 2.5 2 Frequency 1.5 1 0.5 0 (a) 8.0 9.0 10.0 11.0 12.0 (b) 1 7.0 8.0 9.0 10.0 11.0 12.0 13.0 NAME_____Princess Sebo_________________________________________ MAT130 (12) When investigating times required for drive-through service, the following results (in seconds) were obtained. Both restaurants have a mean wait time of 91 seconds for drive-through service. The standard deviations, however, are different. Restaurant A has a standard deviation of 19.12 seconds and Restaurant B has a standard deviation of 33.29 seconds. Restaurant A 108 70 89 97 114 68 Restaurant B 115 126 44 56 98 107 Which restaurant has the most consistent drive-through service times? Explain your choice based on their standard deviations. The following data represent the pulse rates (beats per minute) of nine students enrolled in a section of Statistics Class. The mean pulse rate for the nine students is 73.44 beats per minute and the median is 73. Pulse Rate 73 64 68 81 72 80 82 68 73 (13) Which measure of central tendency would you use to describe this data set, mean or median? Explain your choice. (14) Another student was added to the class after the initial data was collected. Her pulse rate was 108. What type of data point is it considered? Explain. (15)After the pulse rate of 108 was added to the class of rates, the mean changed to 76.9 beats per minute and the median stayed at 73 beats per minute. Which measure of central tendency would you use to describe this data set, mean or median? Explain your choice. 2 NAME_____Princess Sebo_________________________________________ MAT130 (16) SAT mathematics scores have a normal distribution with a mean of 515 and a standard deviation of 114. The normal curve below is labeled with mean and standard deviations along the horizontal axis and empirical rule percentages on the graph. Answer questions (17) - (21) below using the graph of the normal curve. 173 287 401 515 629 743 857 Looking at the Normal Curve above, answer the following questions: (17) What percentage of SAT math scores is between 287 and 629? (18) What percentage of SAT math scores are greater than 401? (19) What percentage of SAT math scores are less than 287? (20) What percentage of SAT math scores are less than 287 or greater than 629? (21) Would it be \"unusual\" for a student to have an SAT mathematics score of 300 or below? Explain. 3 NAME_____Princess Sebo_________________________________________ MAT130 4