The purpose of the quality control sampling of the Widget production lines is to determine whether the lines are malfunctioning or not. Namely, if the mean length of the sample is too different from the population mean of 24 cm and population s = 0.20 cm, maintenance will shut down the production line that was sampled.
Question: Realizing that their sample size is not large enough, quality control now takes 666 Widgets a day off the production line for their sample. One day in March, they find that the sample mean is 24.07 cm. What is the standard error for this sample mean?