Gasoline price
233.792 241.904 229.914 233.217 231.322 234.515 242.899 229.732 232.855 228.998 243.523 233.903 244.615 237.326 234.457 226.436 234.828 238.572 234.140 233.523 242.838 229.900 238.005 239.626 243.159 235.091 224.675 230.180 247.460 239.300 239.342 240.395 237.615 241.114 241.010 239.225 239.434 232.245 245.070 235.830 239.347 232.391 246.407 243.332 239.179 232.724 233.233 240.711 234.083 234.763 241.540 239.211 234.925 238.758 229.826 237.762 232.253 230.775 246.060 239.250
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Resident Commuter 22 18 25 23 18 26 19 19 26 29 22 20 19 20 25 20 20 18 30 30 19 26 19 23 21 21 23 25 27 19 26 23 26 22 18 35 19 21 19 18 23 18 24 22 18 22 29 19 21 19 21 19 26 22 27 28 18 22 19 19 23 36 21 23 28 25 26 25 19 21 22 18 18 27 22 20 26 24 18 20 32 18 18 19 20 27 18 19 24 35 19 24 23 20 22 32 18 20 20 19
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Homeowner Five Years Ago Now 1 17 10 2 20 39 3 29 37 4 43 27 5 36 12 6 43 41 7 45 24 8 19 26 9 49 28 10 49 26 11 35 32 12 16 32 13 23 21 14 33 12 15 44 40 16 44 42 17 28 22 18 29 19 19 39 35 20 22 12 21 27 22 22 38 27 23 37 26 24 33 30 25 38 30 26 33 23 27 32 34 28 32 25 29 36 27 30 28 23 
Q.3 (Show your computations) The U.S. Energy Administration reported that the mean price for a gallon of regular gasoline in the United States was 236.7 cents (U.S. Energy Administration, January 30, 2018). Population Data for regular gasoline prices (cents per gallon) of all 60 service stations in the Lower Atlantic states are contained in the Minitab data file into variable-named Gasoline price. a.) Using Minitab to select a random sample of 32 observations from this population, indicate the random sample of 32 observations, sample mean and sample standard deviation. b.) (1) Formulate the hypotheses that can be used to determine whether the mean price for a gallon of gasoline in the Lower Atlantic states is different from the national mean. (ii) Assume o = 5.4. Indicate an appropriate test statistic and compute its value based on the obtained sample mean in question a.). What are the p-value and your conclusion at a=7%? (iii) Assume o = 5.4. Compute a (100-7) % confidence interval for the population mean gasoline price for your sample of 32 observations. Q.4 (9 marks) (Show your computations) Refer to the obtained data in Q.3., let be the sample proportion of 32 gasoline prices that greater than 236.7 cents per gallon. a.) (2.5 marks) Indicate the random sample proportion of 32 observations and compute the sample proportion. (b.) (4.5 marks) It has been found that 30% of all service stations in the Lower Atlantic state will have the gasoline prices are greater than 236.7 cents per gallon. At a=7%, is there sufficient evidence to conclude that the sample proportion differs from the national percentage? Use the p-value method. (c.)(2 marks) Find a (100-7) % confidence interval of the true proportion. Q.5 Using Minitab in data analysis and answer the questions The dean of students wants to see whether there is a significant difference in ages of resident students and commuting students. She selects a sample of 14 students from each population. Two population data are contained in the Minitab data file into variable-named Resident and Commuter. a.) Using Minitab to select a random sample of 14 observations from each population, indicate the random sample of 14 observations, sample mean and sample standard deviation for each population. b.) Refer to the obtained data in a.), conduct a hypothesis to test the difference between the population variance of ages between the two groups. Given a=9%. c.) Refer to the results from b.), conduct a hypothesis to test the difference between the population mean of ages between resident students and commuting students. Given a=9%. d.) What is the (100-9% confidence interval for the difference between two populations mean ages of resident students and commuting students. Q.6 Using Minitab in data analysis and answer the questions The amount of income spent on housing is an important component of the cost of living. The total costs of housing for homeowners might include mortgage payments, property taxes, and utility costs (water, heat, electricity). Suppose that an economist collected all of 30 homeowners in a district and then calculated these total housing costs as a percent of monthly income, five years ago and now. The population information is reported and contained in the Minitab data file into variable-named Five years ago and Now. a.) Using Minitab to select a random sample of 13 observations from the population, indicate the random sample of 13 observations b.) Is it reasonable to conclude the percent is less now than five years ago? Given a= = 7% (i) State the null and alternative hypotheses. (ii) What is the test statistic? (iii) What is the p-value? (iv) What are the sample mean differences and the sample standard deviation of the differences? (v) What is the conclusion? c.) (2marks) Provide a (100-7) % confidence interval for the mean increase in listening score due to the intensive training. Q.3 (Show your computations) The U.S. Energy Administration reported that the mean price for a gallon of regular gasoline in the United States was 236.7 cents (U.S. Energy Administration, January 30, 2018). Population Data for regular gasoline prices (cents per gallon) of all 60 service stations in the Lower Atlantic states are contained in the Minitab data file into variable-named Gasoline price. a.) Using Minitab to select a random sample of 32 observations from this population, indicate the random sample of 32 observations, sample mean and sample standard deviation. b.) (1) Formulate the hypotheses that can be used to determine whether the mean price for a gallon of gasoline in the Lower Atlantic states is different from the national mean. (ii) Assume o = 5.4. Indicate an appropriate test statistic and compute its value based on the obtained sample mean in question a.). What are the p-value and your conclusion at a=7%? (iii) Assume o = 5.4. Compute a (100-7) % confidence interval for the population mean gasoline price for your sample of 32 observations. Q.4 (9 marks) (Show your computations) Refer to the obtained data in Q.3., let be the sample proportion of 32 gasoline prices that greater than 236.7 cents per gallon. a.) (2.5 marks) Indicate the random sample proportion of 32 observations and compute the sample proportion. (b.) (4.5 marks) It has been found that 30% of all service stations in the Lower Atlantic state will have the gasoline prices are greater than 236.7 cents per gallon. At a=7%, is there sufficient evidence to conclude that the sample proportion differs from the national percentage? Use the p-value method. (c.)(2 marks) Find a (100-7) % confidence interval of the true proportion. Q.5 Using Minitab in data analysis and answer the questions The dean of students wants to see whether there is a significant difference in ages of resident students and commuting students. She selects a sample of 14 students from each population. Two population data are contained in the Minitab data file into variable-named Resident and Commuter. a.) Using Minitab to select a random sample of 14 observations from each population, indicate the random sample of 14 observations, sample mean and sample standard deviation for each population. b.) Refer to the obtained data in a.), conduct a hypothesis to test the difference between the population variance of ages between the two groups. Given a=9%. c.) Refer to the results from b.), conduct a hypothesis to test the difference between the population mean of ages between resident students and commuting students. Given a=9%. d.) What is the (100-9% confidence interval for the difference between two populations mean ages of resident students and commuting students. Q.6 Using Minitab in data analysis and answer the questions The amount of income spent on housing is an important component of the cost of living. The total costs of housing for homeowners might include mortgage payments, property taxes, and utility costs (water, heat, electricity). Suppose that an economist collected all of 30 homeowners in a district and then calculated these total housing costs as a percent of monthly income, five years ago and now. The population information is reported and contained in the Minitab data file into variable-named Five years ago and Now. a.) Using Minitab to select a random sample of 13 observations from the population, indicate the random sample of 13 observations b.) Is it reasonable to conclude the percent is less now than five years ago? Given a= = 7% (i) State the null and alternative hypotheses. (ii) What is the test statistic? (iii) What is the p-value? (iv) What are the sample mean differences and the sample standard deviation of the differences? (v) What is the conclusion? c.) (2marks) Provide a (100-7) % confidence interval for the mean increase in listening score due to the intensive training
