4. More summaries. Here are the annual numbers of deaths from tornadoes in the United States from 1990 through 2000, (Source: NOAA) 25 30 23) 39 399 ( 40 ) 53 17 (69) 94 130 53 39 39 33 69 30 25 67 130 94 40 Find these statistics by hand (no calculator!): a) mean b) median and quartiles c) range and IQR 5. Mistake. A clerk entering salary data into a company spreadsheet accidentally put an extra "0" in the boss's salary, listing it as $2,000,000 instead of $200,000. Explain how this error will affect these summary statistics for the company payroll: a) measures of center: median and mean. b) measures of spread: range, IQR, and standard devi- ation. 6. Sick days. During contract negotiations, a company seeks to change the number of sick days employees may take, saying that the annual "average" is 7 days of ab- sence per employee. The union negotiators counter that the "average" employee misses only 3 days of work each year. Explain how both sides might be correct, identify- ing the measure of center you think each side is using and why the difference might exist. 12 7. Payroll. A small warehouse employs a supervisor at $1200 a week, an inventory manager at $700 a week, six stock boys at $400 a week, and four drivers at $500 a week. a) Find the mean and median wage. b) How many employees earn more than the mean wage? c) Which measure of center best describes a typical wage at this company, the mean or the median? d) Which measure of spread would best describe the payroll, the range, the IQR, or the standard devia- tion? Why