Normal Curve: Tree Rings Tree-ring dates were used extensively in archaeological studies at Burnt Mesa Pueblo (Bandelier Archaeological Excavation.

Project: Summer 1989 Excavations at Burnt Mesa Pueblo, edited by Kohler, Washington State University Department of Anthropology). At one site on the mesa, tree-ring dates (for many samples) gave a mean date of 5year 1272 1 μ with standard deviation s 5 35 1 years. At a second, removed site, the tree-ring dates gave a mean of m 5year 1122 2 with standard deviation s 5 40 2 years. Assume that both sites had dates that were approximately normally distributed. In the first area, an object was found and dated as 5year 1250 1 x .
In the second area, another object was found and dated as 5year 1234 2 x .

(a) Convert both 1 x and 2 x to z values, and locate both of these values under the standard normal curve of Figure 6-15.

(b) Interpretation Which of these two items is the more unusual as an archaeological find in its location?AppendixLO1