Norfolk, Virginia, a major seaport on the East Coast, has a
ship coal-loading facility. Currently, coal trucks filled with
coal arrive at the port facility at the mean rate of 149 per
day (Poisson distributed). The facility operates 24 hours a

day. The coal trucks are unloaded one at a time on a first-
come, first-served basis by automated mechanical equip-
ment that empties the trucks in a constant time of eight

minutes per truck, regardless of truck size. The port author-
ity is negotiating with a coal company for an additional

30 trucks per day. However, the coal company will not use
this port facility unless the port authority can assure them
that their coal trucks will not have to wait to be unloaded at
the port facility for more than 12 hours per truck on the
average. Can the port authority provide this assurance?

Norfolk, Virginia, a major seaport on the East Coast, has a
ship coal-loading facility. Currently, coal trucks filled with
coal arrive at the port facility at the mean rate of 149 per
day (Poisson distributed). The facility operates 24 hours a
day. The coal trucks are unloaded one at a time on a firstcome, first-served basis by automated mechanical equipment that empties the trucks in a constant time of eight
minutes per truck, regardless of truck size. The port authority is negotiating with a coal company for an additional
30 trucks per day. However, the coal company will not use
this port facility unless the port authority can assure them
that their coal trucks will not have to wait to be unloaded at
the port facility for more than 12 hours per truck on the
average. Can the port authority provide this assurance?