Quarters are currently minted with weights normally

Last updated: 7/27/2022

Quarters are currently minted with weights normally distributed and having a standard deviation of 0.062. New equipment is being tested in an attempt to improve quality by reducing variation. A simple random sample of 20 quarters is obtained from those manufactured with the new equipment, and this sample has a standard deviation of 0.048. Use a 0.025 significance level to test the claim that quarters manufactured with the new equipment have weights with a standard deviation less than 0.062. Does the new equipment appear to be effective in reducing the variation of weights? (a) Write the claim mathematically and identify Ho and Ha- A. Ho: 20.062; Ha: o<0.062 (Claim) B. Ho: 20.062 (Claim); Ha: 0 <0.062 C.Ho: o≤ 0.062; Ha: o> 0.062 (Claim) D. Ho: o≤ 0.062 (Claim); Ha: o> 0.062