Question: The weight of a connecting rod used in a diesel engine made at a plant of the General Motors Corporation needs to be strictly uniform to minimize vibrations in the engine. The connecting rod is produced by a forging process. Every day, five rods coming out of the process are selected at random and weighed. The data for 10 days' samples in early 2007 are given below.
On the 10th day, the supervisor stopped the process, declaring it out of control. Prepare one or more appropriate control charts and test whether the process is indeed out of control.