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ABC Company prints text books. They use two modes of transportation to ship, rai

ID: 3248784 • Letter: A

Question

ABC Company prints text books. They use two modes of transportation to ship, rail and truck. In the 20 years during which they have operated, only 2 percent of the packages carried by rail and only 3.5 percent of the packages carried by truck have been lost. The claims manager receives a call and is informed that a package containing text books sent by ABC Company has been lost. ABC sends 60% of the packages by rail and 40% by truck. The text books are indeed lost. What is the probability the text books were shipped by truck? Prove your answer statistically.

Explanation / Answer

P(truck | lost) = P(truck and lost)/P(lost)

= 0.4x0.035/(0.4x0.035 + 0.6x0.02)

= 0.5385

Probability that the text books were shipped by truck = 0.5385