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# Estimation of the Population Proportion and Mean

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Please see attached worksheet. If you can give me detailed formulas with answers it would be great.

1. The local Tupperware dealers earned these commissions last month:

\$4377.47 \$3183.76 \$1970.16 \$2270.88 \$3860.06
\$2508.55 \$1569.64 \$4205.30 \$1663.68 \$3960.71

Assuming the population for the amount of commissions earned by Tupperware dealers last month is known to be normally distributed, create a 95% confidence interval estimate for &#61549;, the mean amount of commission earned.

You will be asked to identify x-bar, s, &#61537;, df, t, E and the confidence interval.
(there are seven questions here---and the two below)

2. Assuming the standard deviation for the cost of a bathroom remodel is known to be \$545. How large a sample would need to be taken to estimate the mean cost of a bathroom remodel to within \$136 with 99% confidence?

3. A researcher is interested in estimating the proportion of employees who are unhappy in their current job. A prior study estimates this proportion at 0.13. How large a sample would need to be taken to estimate this proportion to within 4% with 95% accuracy?