<PRE><B>Question 451934</B>
In 1992, the FAA conducted 86,991 pre-employment drug tests on job applicants who were to be engaged in safety and security-related jobs, and found that 1,143 were positive.

-----------------
p-hat = 1143/86991 = 0.013
---------------------
 (a) Construct a 95 percent confidence interval for the population proportion of positive drug tests
---
SE = 1.96*sqrt[0.013*0.987/86991] = 0.000753
===============
95% CI: 0.013-0.000753 &lt; p &lt; 0.013+0.000753
------
Cheers,
Stan H.
</PRE>