Question

The method of tree-ring dating gave the following years A.D. for an archaeological excavation site. Assume that the population of x values has an approximately normal distribution.

1,250

1,292

1,250

1,194

1,268

1,316

1,275

1,317

1,275

(a)

Use a calculator with mean and standard deviation keys to find the sample mean year x and sample standard deviation s. (Round your answers to the nearest whole number.)

x= _______ A.D.

s= _______ yr

(b)

Find a 90% confidence interval for the mean of all tree-ring dates from this archaeological site. (Round your answers to the nearest whole number.)

lower limit ____ A.D.

upper limit ____ A.D.

Answer 1

The statistic software output for this problem is:

(a)

x = 1271

s = 38

Lower limit = 1247

Upper limit = 1294