Question
In: Statistics and Probability
A survey of 25 randomly selected customers found the ages shown (in years). The mean is...
A survey of 25 randomly selected customers found the ages shown (in years). The mean is 31.96 years and the standard deviation is 10.12 years.
a) Construct a 95% confidence interval for the mean age of all customers, assuming that the assumptions and conditions for the confidence interval have been met.
b) How large is the margin of error?
c) How would the confidence interval change if you had assumed that the standard deviation was known to be 11.0 years?
Solutions
Expert Solution
a) Construct a 95% confidence interval for the mean age of all customers, assuming that the assumptions and conditions for the confidence interval have been met.
In above equation t score is used because sample size (n) < 30.
Where,
b) How large is the margin of error?
c) How would the confidence interval change if you had assumed that the standard deviation was known to be 11.0 years?
Where,
orchestra answered 1 year agoRelated Solutions
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a) Construct a 90% confidence interval for the mean age of all
customers, assuming that the assumptions and conditions for the
confidence interval have been met.
b) How large is...
A survey of 25 randomly selected customers found the ages shown (in years). The mean is...
A survey of 25 randomly selected customers found the ages shown
(in years). The mean is 31.52
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a) Construct a 95% confidence interval for the mean age of
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b) How large is the margin of error?
c) How would the confidence interval change if you had assumed
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A survey of 25 randomly selected customers found the ages shown (in years). The mean is...
A survey of 25 randomly selected customers found the ages shown
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a) Construct a 95% confidence interval for the mean age of all
customers, assuming that the assumptions and conditions for the
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b) How large is the margin of error?
c) How would the confidence interval change if you had assumed
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A survey of 25 randomly selected customers found the ages shown (in years). The mean is...
A survey of 25 randomly selected customers found the ages shown
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a) Construct a 80% confidence interval for the mean age of all
customers, assuming that the assumptions and conditions for the
confidence interval have been met.
b) How large is the margin of error?
c) How would the confidence interval change if you had assumed
that the standard deviation was known to be 10.0 years?
A survey of 25 randomly selected customers found the ages shown (in years). The mean is...
A survey of 25 randomly selected customers found the ages shown
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confidence interval have been met.
b) How large is the margin of error?
c) How would the confidence interval change if you had assumed that
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A survey of 25 randomly selected customers found the ages shown (in years). The mean is...
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A store owner surveyed 25 randomly selected customers and found the ages shown (in years). The...
A store owner surveyed 25 randomly selected customers and found
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Fill in the blanks
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