The observations in exercise 29 were with a new scanner. The long-term alarm
proportion at the security control with the old scanner was 8%.
(a) Has there been a significant increase in the alarm proportion compared to the
old scanner (α = 0:05)?
(b) A second airport also measured the alarm proportion with the same type of
the new scanner and observed 216 alarms among 1800 flight passengers. Is the
alarm proportion significantly different between the two airports (α = 0:05)?