Originally Posted by

**allabout grey** 1.Use margin of error, confidence level, and standard

deviation to find the minimum sample size required to estimate an unknown population mean.

Margin of error: $124, Confidence level; 99%, σ = $560

Do you have a stats book? If so, this formula should be in there:

You are given all the necessary info. E is the margin of error. You should know what sigma and z are. Look up z for a 99% CI in the z table.

2.Find the margin of error for 95% confidence interval used to estimate the population proportion.

In a clinical test with 2333 subjects, 50% showed improvement from the treatment.

Proportions has a minimum sample formula as well.

You have all you need to find E.