See attached file for 3 problems: time for Speedy-Lub oil change, Google manager's salaries, Accu-Copiers' service times 2. The length of time to do a complete full service oil change at Speedy-Lube is normally distributed with a mean of 15.8 minutes and a standard deviation of 2.2 minutes X P(X < x) P(X > x) Mean Std dev 1
See attached file. Using the spreadsheet attached (and please send the completed document back), please use MegaStat to answer the following questions: 1. Do charges incurred by a patient depend on the type of insurance the patient has? If so, how? This is a hypothesis test where we could examine the average charges for pa
8. The following data were collected in a clinical trial to compare a new drug to a placebo for its effectiveness in lowering total serum cholesterol. Generate a 95% confidence interval for the difference in mean total cholesterol levels between treatments. New Drug (n=75), Mean (SD) Total Serum Cholesterol = 185.0
5. A study is run comparing HDL cholesterol levels between men who exercise regularly and those who do not. The data are shown below. Regular Exercise = Yes, N = 35,Mean = 48.5, Std Dev = 12.5 Regular Exercise = No, N =120, Mean = 56.9 ,Std Dev = 11.9 Generate a 95% confidence interval for the differenc
1. The following are body mass index (BMI) scores measured in 12 patients who are free of diabetes and participating in a study of risk factors for obesity. Body mass index is measured as the ratio of weight in kilograms to height in meters squared. Generate a 95% confidence interval estimate of the true BMI. 25, 27, 31 ,33
See Attachment. Marty Rowatti recently assumed the position of director of the YMCA of South Jersey. He would like some current data on how long current members of the YMCA have been members. To investigate, suppose he selects a random sample of 40 current members. The mean length of membership of those in
Please explain all work. In order for a lifestyle change to be considered effective, the target is to have the average cholesterol of this group be below 200. After 6 months of exercising more and eating better, an SRS of 51 patients at risk for heart disease had an average cholesterol of x = 192, with a standard deviation s
Questions A sample of 81 observations is taken from a normal population with a standard deviation of 5. The sample mean is 40. Determine the 95% confidence interval for the population mean. ____________ Dr. Patton is a professor of English. Recently she counted the number of misspelled words in a group of student essays
Confidence interval for the population mean: Use of the t distribution. A toy manufacturer wants to see how long, on average, a new toy captures children's attention. He tests 10 children selected at random and finds that their mean attention span is 33 minutes with a standard deviation of 6 minutes. If we assume that attenti
Average cost of $3,200 for products. n=25. After review it seems mean cost is $2,000 with a standard deviation of $150. Test that average cost is $3,200 or more versus $2,000. assume level of significance of .05. What is the null hypothesis and the alternative hypothesis? What is the critical value and the p-value? What is
Please explain and show all calculations 1. If two large independent samples are taken from two populations, the sampling distribution of the difference between the two sample means can be determined how? 2. In my BMGT 230 class the fall semester is compared with my class 10 years ago. Please answer the following questions
74. Many newspapers, when reporting results of political polls, say that 'with 95% confidence, the results are in error by no more than ±3 percentage points'.The typical sample size is about 1500. The allowance for error is intended to cover both sampling variability and the effect of small biases. a. Assume that the pol
Compute the 99% confidence interval based on four data points that have a sample mean of 71.5 and a sample standard deviation of 16.6032
4. Using the data below, make a histogram, box plot, compute the mean, median, mode and standard deviation City and State Crime Albuquerque, NM 8515 Anaheim, CA 2827 Anchorage, AK 4370 Arlington, TX 5615 Atlanta, GA 10759 Aurora, CO 5079 Austin, TX 6406 Birmingham, AL 7030 Boston, MA 4986 Buffalo, NY 5791 Charlotte,
1 Explain the Central limit theorem in your own words. What is the value of it? What assumption does one have to make when using it? 2 You have a process that has a Mean of 22.5 and a standard deviation of 5.5, taken from a sample survey of n = 25. Produce a 90% confidence interval. Produce a 99% confidence interval. Co
Ranking Factors. In a nationwide survey of 1000 companies with more than 50 employees, managers were asked to rank various factors that influence their decisions in hiring employees. Each factor was ranked on a scale of 1 to 10, with 1 being not important and 10 being very important. The factor "educational background" re
(TCO 7) A marketing firm wants to estimate the average amount spent by patients at the hospital pharmacy. For a sample of 100 randomly selected patients, the mean amount spent was $65.30 and the standard deviation $8.15. (a) Find a 99% confidence interval for the mean amount spent by patients at the pharmacy. Show your calcu
(TCO 7) A drug manufacturer wants to estimate the mean heart rate for patients with a certain heart condition. Because the condition is rare, the manufacturer can only find 18 people with the condition currently untreated. From this small sample, the mean heart rate is 93 beats per minute with a standard deviation of 6. (a)
Tesla Motors needs to buy axles for their new car. They are considering using Chris Cross Manufacturing as a vendor. Tesla's requirement is that 95% of the axles are 100 cm ± 2 cm. The following data is MegaStat output from a test run from Chris Cross Manufacturing. Should Tesla select them as a vendor? Explain your answer.
A random sample a 16 Google managers yield the following information on annual salaries. The sample mean is $69,000, with a sample standard deviation of $4,000. What is the mean salary of all Google managers? What is the 95% confidence interval for the population mean? Confidence interval - mean 95%
1. A consumer group would like to estimate the average amount of P G and E bill for the month of March for single family homes in the San Francisco Bay area. Based on studies conducted in other similar climate cities, the standard deviation is assumed to be $25. The group would like to estimate the average March bill to be withi
1. A sample of 35 golfers showed that their average score on a particular golf course was 80 with a standard deviation of 6. Answer each of the following (show all work): (A) Find the 95% confidence interval of the mean score for all 35 golfers. (B) Find the 95% confidence interval of the mean score for all golfers if this
Why are estimations and confidence intervals important? Do confidence intervals and estimation play a role in the selection of sample size? Please explain your answer.
What is the relationship between confidence intervals and hypothesis testing? How are they the same? How are they different?
1. A researcher wishes to estimate with 99% Confidence, the proportion of adults who have high-speed internet access. Her estimate must be accurate within 5% of the true Proportion. (a) Find the minimum sample needed, using a prior study that found that 54% of the respondents said they have high-speed internet access. (b) No p
1. YOU WORK FOR A CONSUMER ADVOCATE AGENCY AND WANT TO FIND THE MEAN REPAIR COST OF A WASHING MACHINE. AS PART OF YOUR STUDY, YOU RANDOMLY SELECT 55 REPAIR COSTS AND FIND THE MEAN TO BE $131.00. THE SAMPLE STANDARD DEVIATION IS $17.00. COMPLETE PARTS (a) and (b). (a) Construct a 905 confidence interval for the population me
27. A recent study focused on the number of times men and women who live alone buy take-out dinner in a month. The information is summarized below. At the .01 significance level, is there a difference in the mean number of times men and women order take-out dinners in a month? What is the p-value? Statistic Men Women S
Your hospital is negotiating with medical insurance providers, who would like to reduce the amount they pay as reimbursement for hospital stays. For a particular procedure, they would like to reduce payment by $300 and have patients go home one day earlier. To see what effect this would have one hospital costs, a random samp
Attached is the data needed. 1. Test the null hypothesis that the population mean weight loss is zero versus the alternative hypothesis that the mean weight loss is greater than zero. use .05 and assume the population of weight loss is normally distributed. Also compute the p value. 2. What values of the sample mean we
1. Explain why it would not be reasonable to use estimation after a hypothesis test for which the decision was "fail to reject Ho. 2. An elementary school principal would like to know how many hours the students spend watching TV each day. A sample of n = 25 children is selected, and a survey is sent to each child's parents.