please answer the following question on statists

Q #1

4. [-l1 Points] DETAILS BBUNDERSTAT12 3.R.006. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Professor Cramer determines a final grade based on attendance, two papers, three major tests, and a final exam. Each of these activities has a total of 100 possible points. However, the activities carry different weights. Attendance is worth 6%, each paper is worth 9%, each test is worth 13%, and the final is worth 37%. (a) What is the average for a student with 85 on attendance, 65 on the first paper, 95 on the second paper, 95 on test 1, 72 on test 2, 91 on test 3, and 86 on the final exam? (Round your answer to one decimal place.) E (b) Compute the average for a student with the above scores on the papers, tests, and nal exam, but with a score of only 25 on attendance. (Round your answer to one decimal place.) Z Need Help? The pathogen Phytophthora capsici causes bell pepper plants to wilt and die. A research project was designed to study the effect of soil water content and the spread of the disease in fields of bell peppers (Source: Journal of Agricultural, Biological, and Environmental Statistics, Vol. 2, No. 2). It is thought that too much water helps spread the disease. The fields were divided into rows and quadrants. The soil water content (percent of water by volume of soil) was determined for each plot. An important first step in such a research project is to give a statistical description of the data. Soil Water Content for Bell Pepper Study 15 14 14 14 13 12 11 11 11 11 10 11 13 16 10 9 15 12 9 10 7 14 13 14 8 9 8 11 13 13 15 12 9 10 9 9 16 16 12 10 11 11 12 15 6 10 10 10 11 9 LO USE SALT (a) Make a box-and-whisker plot of the data. 20 20 18 18 16 16 14 14 12 12 10 10 CO CO 2- O 0 0(b) Find the interquartile range. _./ (c) Make a frequency table using four classes. class 68 9-11 1214 1517 f l7 ix l4 lxl ll l Then estimate the mean and sample standard deviation using the frequency table. (Round 5 to two decimal places.) = S s = 3 Compute a 75% Chebyshev interval centered about the mean. (Round your answers to two decimal places.) (d) If you have a statistical calculator or computer, use it to nd the actual sample mean and sample standard deviation. (Round 5 to four decimal places.) Need Help? 8. [I1 Points] DETAILS BBUNDERSTAT12 3.R.011. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER A performance evaluation for new sales representatives at Office Automation Incorporated involves several ratings done on a scale of 1 to 10, with 10 the highest rating. The activities rated include new contacts, successful contacts, total contacts, dollar volume of sales, and reports. Then an overall rating is determined by using a weighted average. The weights are 2 for new contacts, 4 for successful contacts, 4 for total contacts, 4 for dollar value of sales, and 5 for reports. What would the overall rating be for a sales representative with ratings of 3 for new contacts, 3 for successful contacts, 1 for total contaci3, 6 for dollar volume of sales, and 8 for reports? (Round your answer to two decimal places.) Need Help? (b) Find the interquartile range. _ (c) Below is the box-and-whisker plot of data from a survey of 20 nurses at Center Hospital. 102030Q506070 Compare this plot with the one in part (a). Discuss the locations of the medians, the locations of the middle halves of the data banks, and the distances from Q1 and Q3 to the extreme values. 12. [OI1 Points] DETAILS PREVIOUS ANSWERS BBUNDERSTAT12 3.1.029. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER When data consist of rates of change, such as speeds, the harmonic mean is an appropriate measure of central tendency. The harmonic mean for n data values, assuming no data value is O, is given by the equation below. Suppose you drive 53 miles per hour for 100 miles, then 66 miles per hour for 100 miles. Use the harmonic mean to nd your average speed. (Round your answer to two decimal places.) n Harmonic mean = E :3: mph Need Help? i X Submit Answer Where does all the water go? According to the Environmental Protection Agency (EPA), in a typical wetland environment, 35% of the water is outflow; 48% is seepage; 8% evaporates; and 9% remains as water volume in the ecosystem (Reference: United States Environmental Protection Agency Case Studies Report 832-R93-005). Chloride compounds as residuals from residential areas are a problem for wetlands. Suppose that in a particular wetland environment the following concentrations (mg/l) of chloride compounds were found: outow, 58.7; seepage, 74.2; remaining due to evaporation, 48.5; in the water volume, 43.4. (a) Compute the weighted average of chlorine compound concentration (mg/l) for this ecological system. (Round your answer to one decimal place.) 43.4 x mg/l (b) Suppose the EPA has established an average chlorine compound concentration target of no more than 58 mg/I. Does this wetlands system meet the target standard for chlorine compound concentration? 0 Yes. The average chlorine compound concentration (mg/I) is too high. 0 Yes. The average chlorine compound concentration (mg/l) is lower than the target. 0 No. The average chlorine compound concentration (mg/l) is lower than the target. G) No. The average chlorine compound concentration (mg/l) is too high. Need Help? The pathogen Phytophthora capsici causes bell pepper plants to wilt and die. A research project was designed to study the effect of soil water content and the spread of the disease in fields of bell peppers (Source: Journal of Agricultural, Biological, and Environmental Statistics, Vol. 2, No. 2). It is thought that too much water helps spread the disease. The elds were divided into rows and quadrants. The soil water content (percent of water by volume of soil) was determined for each plot. An important first step in such a research project is to give a statistical description of the data. Soil Water Content for Bell Pepper Study 15 14 14 14 13 12 11 11 11 11 10 11 13 16 10 9 15 12 9 10 7 14 13 14 8 9 8 11 13 13 15 12 9 10 9 9 16 16 12 10 11 11 12 15 6 10 10 10 11 9 USES (a) Make a box-and-whisker plot of the data. an an 18 18 10 10 14 IA 12 12 10 10 M50\"! M50\"! (b) Find the interquartile range. _ (c) Make a frequency table using four classes. class 68 911 1214 1517 i' l7 lx l4 lxl ll l Then estimate the mean and sample standard deviation using the frequency table. (Round 5 to two decimal places.) ; =E Compute a 75% Chebyshev interval centered about the mean. (Round your answers to two decimal places.) Lower limit :| Upper limit :I (d) [f you have a statistical calculator or computer, use it to find the actual sample mean and sample standard deviation. (Round 5 to four decimal places.) Need Help? _