An industrial engineer collected data on the labor time required to produce an order of automobile mufflers using a heavy stamping machine. The data on times (hours) for n = 52 orders of different parts

has x? = 1.865 hours and s ² = 1.5623 so s = 1.250 hours. What can one assert with 95% confidence about the maximum error if x? = 1.865 hours is used as a point estimate of the true population mean labor time required to run the heavy stamping machine?

2.15 2.27 0.99 0.63 2.45 1.30 2.63 2.20 0.99 1.00 1.05 3.44 0.49 0.93 2.52 1.05 1.39 1.22 3.17 0.85 1.18 2.27 1.52 0.48 1.33 4.20 1.37 2.70 0.63 1.13 3.81 0.20 1.08 292 2.87 262 1.03 2.76 0.97 0.78 4.68 5.20 1.90 0.55 1.00 2.95 0.45 0.70 2.43 3.65 4.55 0.33