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The piston diameter of a certain hand pump is 0.4 inch. The manager determines that the diameters are normally​ distribu

Posted: Wed May 11, 2022 8:05 am
by answerhappygod
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 0.004 inch. After recalibrating the
production​ machine, the manager randomly selects 26 pistons
and determines that the standard deviation is 0.0027 inch. Is there
significant evidence for the manager to conclude that the standard
deviation has decreased at the
α=0.05 level of​ significance?
What is the Null Hypothesis for this test H0?
What is the alternative hypothesis for H1?