A study based on a sample of size 25 reported a mean of 94 with a margin of error of 11 for 95% confidence.
(a) Give the 95% confidence interval.
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(b) If you wanted 99% confidence for the same study, would your margin of error be greater than, equal to, or less than 11? Explain your answer.
The new margin of error would be less than 11. A smaller margin of error is needed to be more confident that the interval includes the true mean.
The confidence level should never be changed for the same study.
It is impossible to determine if the margin of error will change using the information given.
The new margin of error would be equal to 11. The margin of error will not change when the confidence level is increased.
The new margin of error would be greater than 11. A wider margin of error is needed to be more confident that the interval includes the true mean.