Question

The following data represent crime rates per 1000 population for a random sample of 46 Denver neighborhoods.

63.2	36.3	26.2	53.2	65.3	32.0	65.0
66.3	68.9	35.2	25.1	32.5	54.0	42.4
77.5	123.2	66.3	92.7	56.9	77.1	27.5
69.2	73.8	71.5	58.5	67.2	78.6	33.2
74.9	45.1	132.1	104.7	63.2	59.6	75.7
39.2	69.9	87.5	56.0	154.2	85.5	77.5
84.7	24.2	37.5	41.1

(a) Use a calculator with mean and sample standard deviation keys to find the sample mean x and sample standard deviation s. (Round your answers to one decimal place.)

x =	crimes per 1000 people
s =	crimes per 1000 people

(b) Let us say the preceding data are representative of the population crime rates in Denver neighborhoods. Compute an 80% confidence interval for μ, the population mean crime rate for all Denver neighborhoods. (Round your answers to one decimal place.)

lower limit	crimes per 1000 people
upper limit	crimes per 1000 people

(c) Compute a 95% confidence interval for μ, the population mean crime rate for all Denver neighborhoods. (Round your answers to one decimal place.)

lower limit	crimes per 1000 people
upper limit	crimes per 1000 people

Answer 1

The statistical software output for this problem is :

(a)

x = 64.2

s = 27.9

(b)

Lower limit = 58.8

Upper limit = 69.5

(c)

Lower limit = 55.9

Upper limit = 72.4