SCENARIO 18-4
a Factory Supervisor Is Concerned That the Time

question 50

Short Answer

SCENARIO 18-4
A factory supervisor is concerned that the time it takes workers to complete an important production
task (measured in seconds) is too erratic and adversely affects expected profits. The supervisor
proceeds by randomly sampling 5 individuals per hour for a period of 10 hours. The sample mean and
range for each hour are listed below. $$\begin{array} {ccc} \underline {\text { Hour }} & \underline { \bar { X } } & \underline { R } \\1 & 18.4 & 25 \\2 & 16.9 & 27 \\3 & 23.0 & 30 \\4 & 21.2 & 23 \\5 & 21.0 & 24 \\6 & 24.0 & 25 \\7 & 19.3 & 12 \\8 & 15.8 & 14 \\9 & 20.0 & 13 \\10 & 23.0 & 11\end{array}$$ She also decides that lower and upper specification limit for the critical-to-quality variable should be
10 and 30 seconds, respectively.
-Referring to Scenario 18-4, what percentage of the time it takes workers to complete an important
production task will fall inside the specification limits?

---

Definitions:

Urine Test

A diagnostic method that analyzes the content of urine for medical information regarding health and disease.

Selective Permeability

A property of cellular membranes that allows them to regulate the passage of substances in and out of the cell, permitting some molecules to pass through while blocking others.

Loop Of Henle

A section of the nephron in the kidney which concentrates the urine while reabsorbing water and ions.

Water Reabsorption

The process by which water is absorbed back into the bloodstream from the kidneys during urine formation to maintain fluid balance.