If the sample size is increased and the standard deviation and confidence level stay the same, then the margin of error will also be increased. True False

A researcher wants to estimate the average amount of money a person spends on buying lottery tickets each week.  A sample of 50 people who buy lottery tickets was found with a mean of $15 and a standard deviation of 3.4.  Find a 90% confidence interval of the population mean.  Explain in laymen terms what this interval represents. Discuss the basic components of a hypothesis test.

Suppose we want a 99% confidence interval for the average amount spent on books by freshmen in their first year at college. The amount spent has a normal distribution with standard deviation $31. How large should the sample be if the margin of error is to be less than $3?

Collette is self-employed, selling items at Home Interior parties. She wants to estimate the average amount a client spends at each party. A random sample of 35 clients' receipts gave a sample mean of $34.70 and historically we know the population standard deviation of spending at these parties to be $4.85. Explain why you may assume your data is normally distributed. Find a 90% confidence interval for the average amount any given client can be expected to spend at a party