Currently, 25 cent coins are minted with weights that have a mean of 5,670 g and a standard deviation of 0.062 g. New equipment is being tested with the intention of improving quality by reducing variation. A simple random sample of 24 coins minted with the new equipment is obtained; The sample has a standard deviation of 0.049g. Use the sample results to construct an estimate of the 95% confidence interval for the population standard deviation, which is the standard deviation of the weights of the 25-cent coins minted with the new equipment. Based on the confidence interval, does the new equipment appear to produce a clearly smaller standard deviation than the 0.062 g standard deviation of the old equipment? Based on the results, does it appear that the new equipment serves to reduce the variation in weights?
Currently, 25 cent coins are minted with weights that have a mean of 5,670 g and a standard deviation of 0.062 g. New equipment is being tested with the intention of improving quality by reducing variation. A simple random sample of 24 coins minted with the new equipment is obtained; The sample has a standard deviation of 0.049g. Use the sample results to construct an estimate of the 95% confidence interval for the population standard deviation, which is the standard deviation of the weights of the 25-cent coins minted with the new equipment. Based on the confidence interval, does the new equipment appear to produce a clearly smaller standard deviation than the 0.062 g standard deviation of the old equipment? Based on the results, does it appear that the new equipment serves to reduce the variation in weights?
Step by step
Solved in 2 steps with 4 images
