Operations Research Applications and Algorithms (Wayne L. Winston - 4th edition)
Problem: 20.2.6 (p.1063)
Suppose it is equally likely that a plane flight is 50%, 60%, 70%, 80%, or 90% full.
a) What fraction of seats on a typical flight are full? (This is known as flight load factor.)
b) We are always complaining that there are never empty seats on our plane flights. Given the previous information, what is the average load factor on a plane trip I take?