Public Versus Private Childcare Expenses Narrative

Essay

Public versus Private Childcare Expenses Narrative
A social worker was interested in determining whether there is a significant difference in the average monthly cost per child for childcare outside the home between publically supported facilities and privately owned facilities. Two independent random samples were selected, yielding the following information:
-A statistician knows that the population of light bulb lifetimes is normally distributed and has a standard deviation of 30 hours. A simple random sample of 36 bulbs yields a mean lifetime of 504 hours. Construct and interpret a 99% confidence interval for the mean lifetime of all such bulbs.