Discussion:
Q: An estimate is needed of the mean acreage of farms in Manitoba, Canada. The estimate should be correct to within 100 acres with probability 0.95. A preliminary study suggests that 500 acres is a reasonable guess for the standard deviation of farm size.
How large a sample of farms is required and given that random sample size found, The sample has a standard deviation of 300 acres, rather than 500. What is the margin of error for a 95% confidence interval for the mean acreage of farms?