Question
In: Statistics and Probability
We draw a random sample of size 49 from a normal population with variance 2.1. If...
We draw a random sample of size 49 from a normal population with variance 2.1. If the sample mean is 21.5, what is a 99% confidence interval for the population mean?
Solutions
Expert Solution
Solution :
Given that,
Sample size = n = 49
Z
/2
= 2.576
Margin of error = E = Z/2*
(
/
= 2.576 * (1.4491 /
Margin of error = E = 0.5
At 99% confidence interval estimate of the population mean is,
- E < 
<
+ E
21.5 - 0.5 <
< 21.5 + 0.5
21 <
< 22
(21 , 22)
orchestra answered 2 years agoRelated Solutions
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4 We draw a random sample of size 40 from a population with standard deviation 2.5....
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We draw a random sample of size 40 from a population with standard
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Show work in excel with formulas
a
If the
sample mean is 27, what is a 95% confidence interval for the
population mean?
b
If the
sample mean is 27, what is a 99% confidence interval for the
population mean?
c
If the
sample mean is 27, what is a 90% confidence interval for the
population mean?
d
If the
sample mean is 27...
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Repeat part a changing the sample size to 100
What is the affect of increasing the sample size?
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