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A simple random sample with n= 50 provided a sample
a. Develop a 90% confidence interval for the population mean (to 1 decimal).
,
b. Develop a 95% confidence interval for the population mean (to 1 decimal).
,
c. Develop a 99% confidence interval for the population mean (to 1 decimal).
,
d. What happens to the margin of error and the confidence interval as the confidence level is increased?
- Select your answer -
They increase
They decrease
They stay the same
It cannot be determined from the given data
The margin of error increases and the confidence interval becomes narrower
The margin of error decreases and the confidence interval becomes widerItem 7 .
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