The method of tree ring dating gave the following years A.D. for an archaeologic
ID: 3263108 • Letter: T
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. 1215 1306 1257 1278 1268 1316 1275 1317 1275 (a) Use a calculator with mean and standard deviation keys to find the sample mean year x^bar and sample standard deviation s. (Round your answers to the nearest whole number.) x^bar = _________ 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.Explanation / Answer
a) sample Mean = Sum of all observations/9 = 1279
Standard devation = 32
b) For 90% Interval
margin of error = (T.INV(0.95,8)*32)/Sqrt(10) = 19.93447
90% Interval
(1279-19.93447, 1279+19.93447)
(1259, 1298)
Lower Limit : 1259
Upper Limit: 1298