Question

1. If n=28, (x-bar)=49, and s=6, find the margin of error at a 95% confidence level. Give your answer to two decimal places.

2. In a survey, 10 people were asked how much they spent on their child's last birthday gift. The results were roughly bell-shaped with a mean of $39 and standard deviation of $8. Find the margin of error at a 90% confidence level. Give your answer to two decimal places.

3. If n=20, (x-bar)=50, and s=20, construct a confidence interval at a 99% confidence level. Assume the data came from a normally distributed population. Give your answers to one decimal place. ___ < μ < ___

4. If n=24, (x-bar)=36, and s=6, construct a confidence interval at a 90% confidence level. Assume the data came from a normally distributed population. Give your answers to one decimal place. ___ < μ < ___

5. If n=19, (x-bar)=32, and s=3, construct a confidence interval at a 90% confidence level. Assume the data came from a normally distributed population. Give your answers to one decimal place. ___ < μ < ___

Answer 1

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o. 이 0,005 inler kl confidenti 95% -foィ 2-scov e 2 ass)- ラ(Arg)-14-47) 7916 Confidence interbolニ138's , sis

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