Answer Happy

Data show that men between the ages of 20 and 29 in a general population have a mean height of 69.3 inches, with a standard deviation of 2.6 inches. A baseball analyst wonders whether the standard deviation of heights of major-league baseball players is less than 2.6 inches. The heights (in inches) of 20 randomly selected players are shown in the table. Click the icon to view the data table. Test the notion at the x = 0.05 level of significance. What are the correct hypotheses for this test? The null hypothesis is Ho: o The alternative hypothesis is H₁: = 2.6. O < 2.6. Calculate the value of the test statistic. x² = 12.507 (Round to three decimal places as needed.) Use technology to determine the P-value for the test statistic. The P-value is (Round to three decimal places as needed.)

The piston diameter of a certain hand pump is 0.4 inch. The manager determines that the diameters are normally distributed, with a mean of 0.4 inch and a standard deviation of 0.006 inch. After recalibrating the production machine, the manager randomly selects 21 pistons and determines that the standard deviation is 0.0041 inch. Is there significant evidence for the manager to conclude that the standard deviation has decreased at the x = 0.01 level of significance? What are the correct hypotheses for this test? The null hypothesis is Ho: O The alternative hypothesis is H₁: O Calculate the value of the test statistic. x² = 9.339 (Round to three decimal places as needed.) = 0.006. < 0.006. Use technology to determine the P-value for the test statistic. The P-value is