Assignment 1 Math 157 Summer 2016

1 Assignment 1. math 157. Summer 2016. Due 6/2/2016. Question 1. Consider each of the following variables. For each one, state whether it is quantitative or qualitative. Answers to the question How often do you go to the movies? Tick one of the following. (i) At least once a week. (ii) Less than once a week but at least once a month. (iii) Less than once a month but more than once a year. (iv) Less than twice a year.. Answers to the question What state were you born in? . The weight of a baby at birth, given in pounds. Answers to the question How many buses have you travelled on in the last seven days?

2 The social security number for each member of the University of Iowa basketball team. For each day of the year, the difference between the maximum outside temperature recorded at DMACC West Campus and the minimum outside temperature recorded at DMACC. West Campus, given in degrees Celsius. Question 2. In the statements below, identify the population and the sample. A study of 33,043 infants in Italy was conducted to find a link between a heart rhythm abnormality and sudden infant death syndrome. A survey of 1442 adults found that 36% received an influenza vaccine for the current flu season.

3 A survey of 496 students at a college found that 10% planned on traveling out of the country during spring break. A survey of 791 vacationers from the United States found that they planned on spending at least $2000 for their next vacation. At the end of the day, a quality control inspector selects 20 light bulbs from the day's production and tests them. Question 3. Explain which method of data collection you would use to collect data for the study. A study of the effect of a product's warning label to determine whether consumers will still buy the product A study of how fast a virus would spread in a metropolitan area A study of how often people wash their hands in public restrooms Question 4.

4 Determine whether the numerical value is a parameter or a statistic. (a) In a survey of 2253 Internet users, 19% use Twitter or another service to share social updates. (b) At a college, 90% of the Board of Trustees members approved the contract of the new president. (c) A survey of 846 chief financial officers and senior comptrollers shows that 55% of companies are reducing bonuses. Question 5. For the following data, construct the frequency distribution table and histogram. Data set: Highway fuel consumptions (in miles per gallon) for a sample of cars 32 35 28 40 30 42 55 40 45 24.

5 28 34 40 36 34 40 30 25 28 32. 40 35 25 44 26 39 38 42 45 32. Question 6. For the following data, construct a stem-and-leaf plot. Data set: Pulse rates of students in a class 68 105 95 80 90 100 75 70 84 98 102 70. 65 88 90 75 78 94 110 120 95 80 76 108. Question 7. Decide which method of data collection you would use to gather data for each study. Explain your reasoning. (a) A study on the effect of low dietary intake of vitamin C and iron on lead levels in adults. (b) The ages of people living within 500 miles of your home. Question 8. For the following data, calculate the mean, median and mode.

6 The durations (in minutes) of power failures at a residence in the last 10 years 18 26 45 75 125 80 33 40 44 49. 89 80 96 125 12 61 31 63 103 28. Question 9. The average starting salaries (by degree attained) for 25 employees at a company are given. What is the mean starting salary for these employees? 8 with MBAs: $92,500. 17 with BAs in business: $68,000. Question 10. During a quality assurance check, the actual coffee contents (in ounces) of six jars of instant coffee were recorded as , , , , , and (a) Find the mean and the median of the coffee content. (b) The third value was incorrectly measured and is actually Find the mean and median of the coffee content again.

7 (c) Which measure of central tendency, the mean or the median, was affected more by the data entry error?