Chapter 6, Problem 6.2.2CP

Gebhardt Electronics
Gebhardt Electronics produces a wide variety of transformers that it sells directly to manufacturers of electronics equipment. For one component used in several models of its transformers, Gebhardt uses a 3-foot length of .20 mm diameter solid wire made of pure Oxygen-Free Electronic (OFE) copper. A flaw in the wire reduces its conductivity and
increases the likelihood it will break, and this critical component is difficult to reach and repair after a transformer has been constructed. Therefore, Gebhaldt wants to use primarily flawless lengths of wire in making this component. The company is willing to accept more than a 1 in 20 chance that a 3-foot length taken from a spool will be flawless. Gebhaldt also occasionally uses smaller pieces of the same wire in the manufacture of other components, so the 3-foot segments to be used for this component are essentially taken randomly from a long spool of. 20 mm diameter solid OFE copper wire.
Gebhardt is considering a new supplier for wire. This supplier claims that its spools of .20 mm diameter solid OFE copper wire average 50 inches between flaws. Gebhardt must determine whether the new supply will be satisfactory if the supplier's claim is valid.

Managerial Report
In making this assessment for Gebhardt Electronics, consider the following three questions:
2. Using the probability distribution you identified in (1), what is the probability that Gebhardt's criteria will be met (i.e., a 1 in 20 chance that a randomly selected 3-foot segment of wire provided by the new supplier will be flawless)?