TABLE 9-12
A drug company is considering marketing a new local anesthetic. The effective time of
the anesthetic the drug company is currently producing has a normal distribution with a
mean of 7.4 minutes with a standard deviation of 1.2 minutes. The chemistry of the new
anesthetic is such that the effective time should be normally distributed with the same
standard deviation. The company will market the new local anesthetic as being better if
there is evidence that the population mean effective time is greater than the 7.4 minutes
of the current local anesthetic.
Referring to Table 9-12, if you select a sample of 25 new local anesthetics and are
willing to have a level of significance of 0.01, the probability of the company failing to
market the new local anesthetic when its population mean effective time is greater than
the 7.4 minutes is ________ if the population mean effective time is 8 minutes.
TABLE 17-8
The superintendent of a school district wanted to predict the percentage of students
passing a sixth-grade proficiency test. She obtained the data on percentage of students
passing the proficiency test (% Passing), daily mean of the percentage of students
attending class (% Attendance), mean teacher salary in dollars (Salaries), and
instructional spending per pupil in dollars (Spending) of 47 schools in the state.
Following is the multiple regression output with Y = % Passing as the dependent
variable, X1 = % Attendance, X2 = Salaries and X3 = Spending: