A steel mill has been asked to produce highstrength low alloy steel (H. S.L. A.) that has a minimum yieldstrength of 60,000 psi. You are the quality controlsupervisor for the steel mill. As the steel is produced, eachcoil is tested for strength. The data shown at the end of thecase study has been obtained. There are three options tothis case study. Option #1 assumes that you only made onetest per coil. Option #2 assumes you made three tests percoil, and Option #3 assumes you made five tests per coil.
The product is a thin sheet steel that is several feetwide and several thousand feet long. The strip has beenrolled into coils to make them easier to handle. Thesamples are taken from the outside ends of each coil. Thesamples are nominally 0.5 in wide, 0.030 in thick and 2.0 inlong. The sample are tested to yield in tension and the loadat yield is read directly from the load displacement plotproduced by the testing machine. The yield point cannormally be determined within ± 3 pounds.