In rotogravure, a method of printing by rolling paper over engraved, chrome-plated cylinders, the printed paper can be flawed by undesirable lines called bands. Bands occur when grooves form on the cylinder’s surface. When this happens, the presses must be stopped, and the cylinders repolished or replated. The following table gives the number of workdays a printing firm experienced between successive banding shutdowns (39). Fit these data with an exponential model and perform the appropriate goodness-of-fit test at the 0.05 level of significance.
Workdays Between Shutdowns Number Observed 0–1 130
1–2…………………………41
2–3…………………………25
3–4………………………… 8
4–5………………………… 2
5–6………………………… 3
6–7………………………… 1
7–8………………………… 1