A machine has been designed to make nails which are 8cm long with a standard deviation of 0.15cm.A sample of 48 nails is selected periodically to assess if the length is too variable from the standard of 8cm.From the sample of 48 nails,the mean is found to be 7.983cm.Assume the lengths are normally distributed and the standard deviation is known to be 0.15cm.Compute the 95% confidence interval for the population mean nail length.
A)[7.947,8.019]
B)[7.941,8.025]
C)[7.933,8.033]
D)[7.955,8.011]
E)[7.916,8.050]

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The Answer of A machine has been designed to make nails which are 8cm long with a standard deviation of 0.15cm.A sample of 48 nails is selected periodically to assess if the length is too variable from the standard of 8cm.From the sample of 48 nails,the mean is found to be 7.983cm.Assume the lengths are normally distributed and the standard deviation is known to be 0.15cm.Compute the 95% confidence interval for the population mean nail length.
A)[7.947,8.019]
B)[7.941,8.025]
C)[7.933,8.033]
D)[7.955,8.011]
E)[7.916,8.050]

A Machine Has Been Designed to Make Nails Which Are