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.
a) Construct a 95% confidence intervalfor the population proportion of positive drug tests
b) Why is the normality assumption not a problem, despite the very small value of p ?
(Dataare from Flying 120, no. 11 [November, 1993], p. 31)
Neat and step-by-step soltuion is provded.