Treat the seven measurements from each day as a sample and construct an R chart. What does the result suggest?
Refer to the axial loads (pounds) of aluminum Pepsi cans that are 0.0109 in. thick, as listed in Data Set 30 "Aluminum Cans" in Appendix B. An axial load of a can is the maximum weight supported by the side, and it is important to have an axial load high enough so that the can isn't crushed when the top lid is pressed onto the top. There are seven measurements from each of 25 days of production. If the 175 axial loads are in one column, the first 7 are from the first day, the next 7 are from the second day, and so on, so that the "subgroup size" is 7.
Data Set30
CANS 109............ CANS 111
270 ..............................287
273 ..............................216
258 ..............................260
204 ..............................291
254 ..............................210