Lois 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 12 obituaries from newspapers from rural towns in idaho give x¯=81.03 and s=1.53. 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 μ , 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) h0 : ha:

(b) find the test statistic, t =

Yes, this sample provide evidence that people living in rural communities live longer than 77 years.

Step-by-step explanation:

Since we have given that

Average lifespan in the USA = 77 years

We need to check whether the people living in rural communities live longer than 77 years.

So, Hypothesis would be

Since n = 12

since n <30 so, we will use t test.

So, the test statistic value is given by

degrees of freedom = df = n-1 = 12-1 =11

At 95% significance level , t = 1.796

Since, 1.796< 9.125

So, we will reject the null hypothesis.

Hence, Yes, this sample provide evidence that people living in rural communities live longer than 77 years.

arc length = 6.63311 ft.

step-by-step explanation:

the formula the arc measure is:

arc length s=2πr(c)/360

where:

c   is the central angle of the arc in degrees

r   is the radius of the arc

π   is pi, approximately 3.142

using the above formula we get

s =

thus we find that arc length of an arc for a circle of radius 20 feet and central angle 19 degrees is

6.63311 feet