Question
In: Statistics and Probability
Part 1) Suppose Clocks Inc had a random sample of n = 118 measurements is selected...
Part 1) Suppose Clocks Inc had a random sample of n = 118 measurements is selected from a population with mean μ = 25 and standard deviation σ = 9. Find the value of the standard error, σ x ¯ (round to 1 decimal place).
= ?
Part 2) A Clocks Inc made another random sample of 105 students has a test score average of 74 with a standard deviation of 9.3. Find the margin of error if the confidence level is 0.99. (Round answer to two decimal places)
Solutions
Expert Solution
Solution :
Given that,
Part 1)
mean = 
= 25
standard deviation = 
= 9
n = 118
The sampling distribution of mean and standard error is ,
= 25
=
/ 
n = 9 /
118 = 0.8
Part 2)
t
/2,df = 2.624
Margin of error = E = t/2,df
* (s /
= 2.624 * (9.3 /
Margin of error = E = 2.38
orchestra answered 3 years agoRelated Solutions
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Am I wrong or is it the system lol?
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