State the null and alternate hypotheses and find the degree of freedom.
Sue thinks that there is a difference in quality of life between rural and urban living. She collects information from obituaries in newspapers from urban and rural towns in Idaho to see if there is a difference in life expectancy. A sample of 11 people from rural towns give a life expectancy of xr¯=68.4 years with a standard deviation of sr=7.04 years. A sample of 10 people from larger towns give xu¯=74.4 years and su=6.23 years. Does this provide evidence that people living in rural Idaho communities have different life expectancy than those in more urban communities? Use a 5% level of significance.
(a) State the null and alternative hypotheses: (Type ‘‘mu_r″ for the symbol μr , e.g. mu_rnot=mu_u for the means are not equal, mu_r>mu_u for the rural mean is larger, mu_r<mu_u , for the rural mean is smaller. )
H0 = ?