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Question 1 of 20 1.0 Points Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.  Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.  For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.  You are trying to estimate the average amount a family spends on food during a year. In the past, the standard deviation of the amount a family has spent on food during a year has been   $1200. If you want to be 99% sure that you have estimated average family food expenditures within $60, how many families do you need to survey?  Place your answer, a whole number, in the blank          Reset Selection Question 9 of 20 1.0 Points A sample of 23 European countries found that the variance of life expectancy was 7.3 years. What is the 95% confidence interval estimate for the variance of life expectancy in Europe?         Reset Selection Question 10 of 20 1.0 Points In constructing a confidence interval estimate for a population mean, when we replace  with the sample standard deviation (s), we introduce a new source of variability and the sampling distribution we use is:         Reset Selection Question 11 of 20 1.0 Points Find the 95% confidence interval for the standard deviation of the lengths of pipes if a sample of 26 pipes has a standard deviation of 10 inches.         Reset Selection Question 12 of 20 1.0 Points If you are constructing a confidence interval for a single mean, the confidence interval will___________ with an increase in the sample size.         Reset Selection Question 13 of 20 1.0 Points The average gas mileage of a certain model car is 26 miles per gallon. If the gas mileages are normally distributed with a standard deviation of 1.3, find the probability that a randomly selected car of this model has a gas mileage between 25.8 and 26.3 miles per gallon.         Reset Selection Question 14 of 20 1.0 Points Confidence intervals are a function of which of the following three things?         Reset Selection Question 15 of 20 1.0 Points The t- distribution for developing a confidence interval for a mean has _____ degrees of freedom.         Reset Selection Question 16 of 20 1.0 Points A researcher wishes to know, with 98% confidence, the percentage of women who wear shoes that are too small for their feet. A previous study conducted by the Academy of Orthopedic Surgeons found that 80% of women wear shoes that are too small for their feet. If the researcher wants her estimate to be within 3% of the true proportion, how large a sample is necessary?         Reset Selection Question 17 of 20 1.0 Points From a sample of 500 items, 30 were found to be defective. The point estimate of the population proportion defective will be:         Reset Selection Question 18 of 20 1.0 Points Which of the following will make a confidence interval narrower and more precise?         Reset Selection Part 3 of 3 -   Question 19 of 20 1.0 Points The 95% confidence interval for the population mean  , given that the sample size n = 49 and the population standard deviation    = 7, is  . Reset Selection Question 20 of 20 1.0 Points As a general rule, the normal distribution is used to approximate the sampling distribution of the sample proportion, , only if the sample size n is greater than 30.

the following is the number of each color of M&M found in a sample bag of 280 M&M's. Red= 39 Orange= 58 Yellow= 55 Green= 38 Blue= 27 Brown= 63 suppose you reach into the bag and randomly select one M&M. Calculate the following probabilities.  P(red)= p(yellow)= p(Blue)=   4. the probability that the first M&M is red, the second M&M is yellow, and the third M&M is blue. ( with replacement)   5. the probability that the first M&M is red, the second M&M is yellow, and the third M&M is blue. (without replacement)   6. the probability that all three M&M's are blue. ( with replacement)   7. the probability that all three M&M's are blue. (without replacement)   6.

Attached statistics Q&A

10.11 An important feature of tablets is battery life, the num-ber of hours before the battery needs to be recharged. The file Tablets contains the battery life of 12 WiFi-only and 7 3G/4G/WiFi 9- through 12-inch tablets. (Data extracted from “Ratings and rec-ommendations: Tablets,” Consumer Reports, August 2013, p. 24. )a. Assuming that the population variances from both types of tablets are equal, is there evidence of a difference in the mean battery life between the two types of tablets? 1Use a=0.05.2 b. Determine the p-value in (a) and interpret its meaning. c. Assuming that the population variances from both types of tablets are equal, construct and interpret a 95% confidence interval estimate of the difference between the population mean battery life of the two types of tablets.   10.17 Brand valuations are critical to CEOs, financial and marketing executives, security analysts, institutional investors, and others who depend on well-researched, reliable information needed for assessments, and comparisons in decision making. Millward Brown Optimor has developed the BrandZ Top 100 Most Valuable Global Brands for WPP, the world’s largest com-munications services group. Unlike other studies, the BrandZ Top 100 Most Valuable Global Brands fuses consumer measures of brand equity with financial measures to place a financial value on brands. The file BrandZTechFin contains the brand values for two sectors in the BrandZ Top 100 Most Valuable Global Brands for 2014: the technology sector and the financial institutions sector. (Data extracted from bit.ly/18OL5Mu.) a. Assuming that the population variances are equal, is there evi-dence of a difference between the technology sector and the financial institutions sector with respect to mean brand value? (Use a=.05. b. Repeat (a), assuming that the population variances are not equal. c. Compare the results of (a) and (b).   10.23 What motivates employees? The Great Place to Work Institute evaluated nonfinancial factors both globally and in the United States. (Data extracted from L. Petrecca, “Tech Companies Top List of ‘Great Workplaces,’” USA Today, October 31, 2011, p. 7B.) The results, which indicate the importance rating of each factor, are stored in Motivation . a. At the 0.05 level of significance, is there evidence of a differ-ence in the mean rating between global and U.S. employees? b. What assumption is necessary about the population distribution in order to perform this test? c. Use a graphical method to evaluate the validity of the assump-tion in (b).   10.45 A problem with a telephone line that prevents a customer from receiving or making calls is upsetting to both the customer and the telecommunications company. The file Phone contains samples of 20 problems reported to two different offices of a tele-communications company and the time to clear these problems (in minutes) from the customers’ lines. a. At the 0.05 level of significance, is there evidence of a differ-ence in the variability of the time to clear problems between the two central offices? b. Determine the p-value in (a) and interpret its meaning. c. What assumption do you need to make in (a) about the two populations in order to justify your use of the F test? d. Based on the results of (a) and (b), which t test defined in Sec-tion 10.1 should you use to compare the mean time to clear problems in the two central offices?

The safety director of large steel mill took samples at random from company records of minor work-related accidents and classified them according to the time the accident took place.     Number of     Number of   Time Accidents    Time Accidents   8 up to 9 A.M.   7      1 up to 2 P.M.   6     9 up to 10 A.M.   9      2 up to 3 P.M.   6     10 up to 11 A.M.   18      3 up to 4 P.M.   22     11 up to 12 P.M.   6      4 up to 5 P.M.   9     Using the goodness-of-fit test and the 0.05 level of significance, determine whether the accidents are evenly distributed throughout the day. (Round your answers to 3 decimal places.)

A landscaper wants to plant begonias along the edges of a triangular plot of land in Winton Woods Park. Two of the angles of the triangle measure 95?and 40?. The side between the two angles is 80 feet long. What is the perimeter of this triangular plot of land?

  Question 1 of 20 1.0 Points A sample of 20 observations has a standard deviation of 4. The sum of the squared deviations from the sample mean is:   A. 320   B. 304   C. 288   D. 400 Reset Selection Question 2 of 20 1.0 Points Suppose that a histogram of a data set is approximately symmetric and "bell shaped". Approximately, what percent of the observations are within three standard deviations of the mean?   A. 50%   B. 99.7%   C. 95%   D. 68% Reset Selection Question 3 of 20 1.0 Points Which of the following correctly describes the relationship between a sample and a population?    A. A sample is a group of populations that are subject to observation.    B. A population and a sample are not related.    C. A population is a group of samples that may or may not be included in a study   D. A sample is a group of subjects selected from a population to be studied.  Reset Selection Question 4 of 20 1.0 Points A histogram that has a single peak and looks approximately the same to the left and right of the peak is called:   A. bimodal   B. symmetric   C. proportional   D. balanced Reset Selection Question 5 of 20 1.0 Points Which of the following statements is true for the following data values: 7, 5, 6, 4, 7, 8, and 12?   A. Only the mean and median are equal   B. The mean, median and mode are all equal   C. Only the median and mode are equal   D. Only the mean and mode are equal Reset Selection Question 6 of 20 1.0 Points If a variable has possible values –2, 6, and 17, then this variable is    A. both a continuous and a discrete variable   B. a discrete variable   C. neither a continuous nor a discrete variable   D. a continuous variable Reset Selection Question 7 of 20 1.0 Points Which of the following statements is true regarding the data set 10, 10, 10, 10, and 10?   A. The range is zero   B. The standard deviation equals zero   C. The interquartile range equals zero   D. all of the above Reset Selection Question 8 of 20 1.0 Points Gender and State are examples of which type of data?   A. Discrete data   B. Continuous data   C. Categorical data   D. Ordinal data Reset Selection Question 9 of 20 1.0 Points If a value represents the 95th percentile, this means that   A. 95% of the time you will observe this value   B. 95% of all values are below this value   C. 95% of all values are above this value    D. there is a 5% chance that this value is incorrect Reset Selection Question 10 of 20 1.0 Points A scatter plot would be useful for   A. Showing the trend of sales, over time, of five different brands of blank DVDs    B. Showing the relationship between the sales of blank CDs and blank DVDs    C. Showing the top selling brands of blank DVDs   D. Showing the relative number of sales of four different brands of blank DVDs Reset Selection Question 11 of 20 1.0 Points Which of the following indicates how many observations fall into various categories?   A. The frequency table   B. The tabulation scale   C. The Likert scale   D. The sample table Reset Selection Question 12 of 20 1.0 Points Which of the following are the three most common measures of central location?   A. Mean, median, and standard deviation   B. Mean, median, and mode   C. Mean, variance, and standard deviation   D. Mean, median, and variance Reset Selection Part 2 of 3 -    Question 13 of 20 1.0 Points Click to see additional instructions A sample of 150 students at a State University was taken after the final business statistics exam to ask them whether they went partying the weekend before the final or spent the weekend studying, and whether they did well or poorly on the final. The following table contains the result.     Did Well in Exam Did Poorly in Exam Studying for Exam 60 15 Went Partying 22 53      Question 14 of 20 1.0 Points Click to see additional instructions The following data are the base salaries, in thousands of dollars, of 50 chief executive officers for a sample of companies doing business with the state of Connecticut. That is, the first entry in the table below corresponds to a salary of $125,000. A copy of this data set can be found in the Excel Workbook called CEOSalaries.xls. 125 157 113 127 201 165 145 119 148 158 148 168 117 105 136 136 125 148 108 178 179 191 225 204 104 205 197 119 209 157 209 205 221 178 247 235 217 222 224 187 265 148 165 228 239 245 152 148 115 150         Find the median of the CEO salaries, in thousands of dollars, rounded to 2 decimal places. Do not use a dollar sign. Note: $177,760 should be recorded as 177.76.     Question 15 of 20 1.0 Points Click to see additional instructions    Question 16 of 20 1.0 Points Click to see additional instructions The following data are the base salaries, in thousands of dollars, of 50 chief executive officers for a sample of companies doing business with the state of Connecticut. That is, the first entry in the table below corresponds to a salary of $125,000. A copy of this data set can be found in the Excel Workbook called CEOSalaries.xls. 125 157 113 127 201 165 145 119 148 158 148 168 117 105 136 136 125 148 108 178 179 191 225 204 104 205 197 119 209 157 209 205 221 178 247 235 217 222 224 187 265 148 165 228 239 245 152 148 115 150         Find the interquartile range of the CEO salaries, in thousands of dollars, rounded to 2 decimal places. Do not use a dollar sign. Note: $177,760 should be recorded as 177.76.     Question 17 of 20 1.0 Points Click to see additional instructions A sample of 150 students at a State University was taken after the final business statistics exam to ask them whether they went partying the weekend before the final or spent the weekend studying, and whether they did well or poorly on the final. The following table contains the result.     Did Well in Exam Did Poorly in Exam Studying for Exam 60 15 Went Partying 22 53    Question 18 of 20 1.0 Points Click to see additional instructions A sample of 150 students at a State University was taken after the final business statistics exam to ask them whether they went partying the weekend before the final or spent the weekend studying, and whether they did well or poorly on the final. The following table contains the result.   Did Well on Exam Did Poorly on Exam Studying for Exam 60 15 Went Partying 22 53 If the sample is a good representation of the population, what percentage of those who did poorly on the final exam should we expect to have spent the weekend studying?  Place your answer in the blank, rounded to 2 decimal places. Do not use a percentage sign (%). For example, 44.44 would be a legitmate answer.     Part 3 of 3 -    Question 19 of 20 1.0 Points A histogram is skewed to the left (or negatively skewed) if it has a single peak and the values of the distribution extend much further to the right of the peak than to the left of the peak. Reset Selection Question 20 of 20 1.0 Points If you are in a class where most students do reasonably well on a test but a few pull down the class average, the histogram describing the test scores will indicate a positively-skewed distribution. Reset Selection