Question

Katie thinks that people living in a rural environment have a healthier lifestyle than other people. She believes the average lifespan in the USA is 77 years. A random sample of 20 obituaries from newspapers from rural towns in Idaho give ?¯=77.73 and ?=0.62. Does this sample provide evidence that people living in rural Idaho communities live longer than 77 years?

(a) State the null and alternative hypotheses: (Type "mu" for the symbol ?, e.g.  mu >1 for the mean is greater than 1,  mu < 1 for the mean is less than 1, mu not = 1 for the mean is not equal to 1)
?0 :  
?? :

(b) Find the test statistic, t =

Answer 1

Solution :

This is the two tailed test,  

The null and alternative hypothesis is ,

H0 :   = 77

Ha : > 77

Test statistic = t =

= ( - ) / s / n

= (77.73 - 77) / 0.62 / 20

Test statistic = t  = 5.27