SCENARIO 18-8
Recently, a University Switched to a New Type

Short Answer

SCENARIO 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. $$\begin{array} { r l r l } \underline { \text { Day } } & \text { Range } & \underline { \text { Mean } } & \underline { \text { Std.Dev. } } \\1 & 10 & 5.250 & 3.4949 \\2 & 31 & 15.250 & 10.3060 \\3 & 13 & 20.375 & 4.9262 \\4 & 21 & 22.875 & 8.3911 \\5 & 35 & 8.500 & 11.3767 \\6 & 18 & 7.875 & 6.9372 \\7 & 25 & 11.250 & 8.5815 \\8 & 30 & 7.875 & 9.5235 \\9 & 17 & 10.250 & 6.3640 \\10 & 22 & 9.500 & 7.8740 \\11 & 27 & 7.875 & 8.7086 \\12 & 26 & 12.875 & 9.3723\end{array}$$
-Referring to Scenario 18-8, an $\bar { X }$ chart is to be used for the time required to register. The lower
control limit for this data set is ________, while the upper control limit is ________.