Question: A new machine has just been installed to cut and rough-shape large slugs. The slugs are then transferred to a precision grinder. One of the critical measurements is the outside diameter. The quality control inspector randomly selected five slugs each half-hour, measured the outside diameter, and recorded the results. The measurements (in millimeters) for the period 8:00 a.m. to 10:30 a.m. follow.

Time 1 2 3 4 5

8:00 87.1 87.3 87.9 87.0 87.0

8:30 86.9 88.5 87.6 87.5 87.4

9:00 87.5 88.4 86.9 87.6 88.2

9:30 86.0 88.0 87.2 87.6 87.1

10:00 87.1 87.1 87.1 87.1 87.1

10:30 88.0 86.2 87.4 87.3 87.8