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. 1285 1222 1313 1236 1268 1316 1275 1317 1275 (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

a)

mean xbar =1279

s =34.00

b)

from above: 90% confidence interval for the mean

lower limit=1257 ( please try 1258 if this comes wrong and revert)

upper limit= 1300