Please show all the work and the methods used so that i may learn the step by step process and understand. Thank you
1.In a SRS of 30 subway cars during rush hour, the average number of riders per car was 82.5 with a standard deviation of 4.7 (assume the sample data was approximately normal). Establish and interpret a 90% confidence interval for the average number of riders per car during rush hour.
2.A building inspector inspects 245 homes and finds 41 with serious code violations. Construct and interpret a 99% confidence interval for the true proportion of homes with serious violations.
3.An automotive company executive claims that a mean of 51.3 cars per dealership are sold each month. A major stockholder believes this is high and tests the hypothesis by sampling 35 dealerships. What conclusions can be reached if the data shows an average of 45.4 cars with a standard deviation of 15.4?
4.A manufacturing process is supposed to produce nails that are 3.25 inches in length. To test the machine producing the nails, a sample of 150 nails shows an average length of 3.17 inches with a standard deviation of 0.09. Is this significant evidence that the machine is not working properly?
1.In a SRS of 30 subway cars during rush hour, the average number of riders per car was 82.5 with a standard deviation of 4.7 (assume the sample data was approximately normal). Establish and interpret a 90% confidence interval for the average number of riders per car during rush hour.
2.A building inspector inspects 245 homes and finds 41 with serious code violations. Construct and interpret a 99% confidence interval for the true proportion of homes with serious violations.
3.An automotive company executive claims that a mean of 51.3 cars per dealership are sold each month. A major stockholder believes this is high and tests the hypothesis by sampling 35 dealerships. What conclusions can be reached if the data shows an average of 45.4 cars with a standard deviation of 15.4?
4.A manufacturing process is supposed to produce nails that are 3.25 inches in length. To test the machine producing the nails, a sample of 150 nails shows an average length of 3.17 inches with a standard deviation of 0.09. Is this significant evidence that the machine is not working properly?