Question

Jury Selection: One study of grand juries in Alameda County, California, compared the demographic characteristics of jurors with the general population, to see if jury panels were representative. The observed results and the demographic percentages for each age group are shown below. The investigators wanted to know if the jurors were selected at random from the population of Alameda County. (Only persons over 21 and over are considered; the county age distribution is known from Public Health Department data.) Given the following data and an a=.10, do we have evidence that grand juries were selected at random for the population of Alameda County?

                                   

Age	County-Wide Percentage	Observed Number of Jurors
21-40	22%	61
41-50	33%	29
51-60	38%	59
over 60	7%	14
Total	100%	163

Answer 1