Q1) Determine 95% confidence interval of true difference in the means. Sociologist wish to determine if life expectancy of people in Africa is less than life expectancy of people in Asia. Data obtained is shown in table below. Use α = 0.05
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Africa
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Asia
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|
X‾
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55.3
|
65.2
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σ
|
8.1
|
9.3
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|
N
|
53
|
42
|
a) -13.46 <µ1 - µ2 <-6.34
b) -16.33 <µ1 - µ2 <-5.98
c) -12.16 <µ1 - µ2 <-6.86
d) -11.35 <µ1 - µ2 <-7.58
2) In comparing two variances below, determine test value and what are degrees of freedom that must be used?
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Variance
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Number of values
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Sample 1
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6
|
18
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|
Sample 2
|
11
|
29
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a) Test value = 1.83, degrees of freedom = 18 and 29
b) Test value = 1.83, degrees of freedom = 17 and 28
c) Test value = 0.55, degrees of freedom = 18 and 29
d) Test value = 0.55, degrees of freedom = 17 and 28