Explain
why the times are a population.
These times are considered a population
because all of the times from Saturday night are listed instead of a small
sample of the times.
Find
the mean and median of the times.
Mean=1021/25=40.84
Median= 39 which is the midpoint of the
population when listed in order from highest to lowest or lowest to highest
values.
Find
the range and standard deviation of the times.
Range=44
STDEV.P
14.54
82. The following frequency distribution reports
the electricity costs for a sample of 50 two-bedroom apartments in Albuquerque,
New Mexico during the month of May last year.
Cost Frequency (M) (fM) M-x^2 (M-x^2)^2 f(M-x^2)^2
80 to
100 3 90 270 -87 7569 22707
100 to
120 8 110 880 -102 10404 83232
120 to
140 12 130 1560 -118 13924 167088
140 to
160 16 150 2400 -134 17956 287296
160 to
180 7 170 1190 -163 26569 185983
180
to 200 4 190 760 -186 34596 138384
Total 50 7060 884690
Mean STDEV.S
141.2 26.235
Empirical Rule
141.20 (+)(-) 2*26.235 = 141.20 (+)(-)
52.47 = 193.67, 88.73 (95% lie within 2 standard deviations of the mean)
87. Refer to the Real Estate data, which reports
information on homes sold in Denver, Colorado, area last year.
I.
Select the variable selling price.
a.
Find the mean, median, and the standard deviation.
Mean 221.10
Median 213.6
STDEV. 47.11
b.
Write a brief summary of the distribution of the area of homes.
The distribution is symmetric because the mean rounded
would be $220,000.
II.
Select the variable referring to the area of the home in square feet.
Find
the mean, median, and the standard deviation.