Answer:
a
b
Ca
Cb
Explanation:
From the question we are told that
The sample size is n = 100
The upper limit of the 95% confidence interval is b = 47.2 years
The lower limit of the 95% confidence interval is a = 34.5 years
Generally the sample mean is mathematically represented as
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Generally the margin of error is mathematically represented as
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Considering question C a
From the question we are told the confidence level is 90% , hence the level of significance is
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The sample size is n = 22
Given that the sample size is not sufficient enough i.e we will make use of the student t distribution table
Generally the degree of freedom is mathematically represented as
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Generally from the student t distribution table the critical value of at a degree of freedom of 21 is
Considering question C b
From the question we are told the confidence level is 80% , hence the level of significance is
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Generally from the normal distribution table the critical value of is