TABLE 18-8
Recently, a University Switched to a New

question 55

Short Answer

TABLE 18-8
Recently, a university switched to a new type of computer-based registration. The registrar is concerned with the amount of time students are spending on the computer registering under the new system. She decides to randomly select 8 students on each of the 12 days of the registration and determine the time each spends on the computer registering. The range, mean, and standard deviation of the times required to register are in the table that follows.
$$\begin{array} { c c l l } \text { Day } & \text { Range } & \text { Mean } & \text { Std.Dev. } \\1 & 10 & 5.250 & 3.4949 \\2 & 31 & 15.250 & 10.3060 \\3 & 13 & 20.375 & 4.9262 \\4 & 21 & 22.875 & 8.3911 \\5 & 35 & 8.500 & 11.3767 \\6 & 18 & 7.875 & 6.9372 \\7 & 25 & 11.250 & 8.5815 \\8 & 30 & 7.875 & 9.5235 \\9 & 17 & 10.250 & 6.3640 \\10 & 22 & 9.500 & 7.8740 \\11 & 27 & 7.875 & 8.7086 \\12 & 26 & 12.875 & 9.3723\end{array}$$
-Referring to Table 18-8, an R chart is to be constructed for the time required to register. One way to create the upper control limit involves multiplying the average of the sample ranges by D4. For this data set, the value of D4 is______ .

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Definitions:

General-purpose Table

A table designed to organize and display information for a broad range of uses or applications.

Titles

Words or phrases that are used to designate books, articles, artworks, positions, or other works and entities.

Flowchart

A diagram that illustrates the sequence of operations to be performed to get to the solution of a particular problem.

Hierarchy

A system or organization in which people or groups are ranked one above the other according to status or authority.