Question

At a certain excavation site, archaeological studies have used the method of tree-ring dating in an effort to determine when people lived in there. wood from several excavations gave a mean of (year) 619 with a standard deviation of 42 years. the distribution of dates was more or less mound-shaped and symmetrical about the mean. use the empirical rule to estimate a range of years centered about the mean in which about 99.7% of the data (tree-ring dates) will be found.

Answer 1

The range of years would be 493 to 745.

According to the empirical rule, 99.7% of data will fall within 3 standard deviations from the mean.  Using this information, we have

619+3(42) and 619-3(42)
619+126 and 619-126
745 and 493