Chapter 3, Problem 13CR

Political Science: Georgia Democrats How Democratic is Georgia? County-by-county results are shown for a recent election. For your convenience. the data have been sorted in increasing order (Source: Countyand City Data Book. 12th edition. U.S. Census Bureau).

Percentage of Democratic Vote by Counties in Georgia

31	33	34	34	35	35	35	36	38	38	38	39	40	40	40	40
41	41	41	41	41	41	41	42	42	43	44	44	44	45	45	46
46	46	46	47	48	49	49	49	49	50	51	52	52	53	53	53
53	53	55	56	56	57	57	59	62	66	66	68

(a) Make a bos-and-whisker plot of the data. Find the interquartile range.

(b) Grouped Data Make a frequency table using five classes. Then estimate the mean and sample standard deviation using the frequency table. Compute a 75% Chebyshev interval centered about the mean.

(c) If you have a statistical calculator or computer, use it to find the actual sample mean and sample standard deviation. Otherwise, use the values $\sum x=2769\text{ and }\sum x^2=132,179$ to compute the sample mean and sample standard deviation.