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Answers
Chapter 2
1.
(a) 41.6, 35, 35, mean is high due to one large observation
(b) 11.6, 12, 12, little to choose between them
(c) 14.1, 14, 14, little to choose between them
2.
Medians – A (13), B (15) the mean is distorted by extreme values
3.
(a) 1.55, 1.04 (b) 45.6, 45.8 (c) 3.79, 3
4.
22.3 years
5.
yes - mean age = 8.6 months
6.
(a)
Age
40 - 49 50 - 59 60 - 69 70 - 79 80 – 89
Frequency
4
4
3
2
7
(b) 67
(c) 66.75 (d) some accuracy lost in grouping
7.
(a) 322.33 (b) 326.93
8.
(a) 31.19 (2 d.p.)
9.
(b)
(a) $118.93
31
(b) $126.60
(c) $142.25
10.
Median = 722.5 miles mean = 709.1 mile
Both measures are equally - difference between them may be considered small
11.
(a) 60.83
12.
Median = $877.67
(b) 60.89 each equally good
mean = $853.61