It has been reported that the standard deviation of the speeds of drivers on Interstate 75...

It has been reported that the standard deviation of the speeds of drivers on Interstate 75 near Tifton, GA is 8 mph for all vehicles. A Department of Transportation engineer claims this is too low. A survey is conducted and for 30 drivers, the standard deviation is 10.5 mph. At  = 0.05 , is the engineer correct?

State:__________________________________ CV: use table E, F, G, CV=___________________ TV: z, t, or 2  (circle one), TV=________________ Decide:_________________________________ Summary: (remember to circle the correct description before completing the statement) There is/is not enough evidence to reject/support the claim that______________________ ________________________________________________________________________ _______________________________________________________________________

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Expert Solution

There is enough evidence to reject/support the claim that standard deviation is as low as 8 mph.

orchestra answered 1 year ago

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