8.
The U
.
S
.
Department of Transportation reported that
in 2009, Southwest led all domestic airlines
in on
-
time arrivals
for domestic flights, with a rate of 0
.
825
.
Using the
binomial distribution, what
is the probability that in the
next six flights
a.
four flights will be on time?
b.
all six flights will be on time?
c.
at least four flights will be on time?
d.
What are the mean and standard deviat
ion of the number of on-time arrivals?
e.
What assumptions do you need to make in (a) through (c)?