1415*98+6+7655 a machine produces metal rods used in an automobile suspension system. a random sample of 15 rods is selected and the diameter is measured. the resulting data (in millimeters) are as follows: no. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 dia. 8.21 8.19 8.23 8.25 8.26 8.23 8.20 8.26 8.19 8.23 8.20 8.28 8.24 8.25 8.24 use the data above to calculate a 95% two-sided confidence interval on the mean rod diameter. assume the data are normally distributed. (a) calculate the sample mean and standard deviation.

1415*98+6+7655 A machine produces metal rods used in an automobile suspension system. a random sample of 15 rods is selected and the diameter is measured. the resulting data (in millimeters) are as follows: no. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 dia. 8.21 8.19 8.23 8.25 8.26 8.23 8.20 8.26 8.19 8.23 8.20 8.28 8.24 8.25 8.24 use the data above to calculate a 95% two-sided confidence interval on the mean rod diameter. assume the data are normally distributed. (a) calculate the sample mean and standard deviation.

1415*98+6+7655 A machine produces metal rods used in an automobile suspension system. a random sample of 15 rods is selected and the diameter is measured. the resulting data (in millimeters) are as follows: no. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 dia. 8.21 8.19 8.23 8.25 8.26 8.23 8.20 8.26 8.19 8.23 8.20 8.28 8.24 8.25 8.24 use the data above to calculate a 95% two-sided confidence interval on the mean rod diameter. assume the data are normally distributed. (a) calculate the sample mean and standard deviation.