Randomly selected statistics students of the author participated in an experiment to test their ability to determine when 60 seconds had passed. Forty students yielded a sample mean of 58.3 seconds. Assume that σ = 9.5 seconds.
a. Find the best point estimate of the meantime for all statistics students. Use the correct symbol.

b. Find the z a/2 for a 78% confidence level. (Don’t do the entire interval – just find the z)

z d/2 = InvNorm (1-0.11) = 1.23 *Show the steps to get this number

c. What is the preferred method of estimation? Point Estimate or Confidence Interval