Yahoo Answers: Answers and Comments for Estimation & The CLT? [Mathematics]
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enUS
Mon, 27 Feb 2012 12:11:26 +0000
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Yahoo Answers: Answers and Comments for Estimation & The CLT? [Mathematics]
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https://answers.yahoo.com/question/index?qid=20120227121126AAvuTGe
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From cidyah: a)
μ = 162
σ = 3.5
standardize x to z = (x ...
https://answers.yahoo.com/question/index?qid=20120227121126AAvuTGe
https://answers.yahoo.com/question/index?qid=20120227121126AAvuTGe
Tue, 28 Feb 2012 15:31:30 +0000
a)
μ = 162
σ = 3.5
standardize x to z = (x  μ) / σ
P(x > 163) = P( z > (163162) / 3.5)
= P(z > 0.2857) = .3859
(From Normal probability table)
b)
Mean μ = 162
Standard deviation σ = 3.5
Standard error σ / √ n = 3.5 / √ 10 = 1.1067972
standardize xbar to z = (xbar  μ) / (σ / √ n )
P(xbar > 163) = P( z > (163162) / 1.106797)
= P(z > 0.9035) = .1841
(from normal probability table)
c)
From (a) , for one boy, the probability is .3859
For all 10 boys , the probability of height > 163cm = (.3859)^10 = .0000732