The concentrates were pooled from the blood of about 1000 donors per lot. If the prevalence of HIV in donor blood in the early 1980s was 1 in 3,000, what was the probability that a hemophiliac would contract HIV from a single infusion of clotting factors?

The required probability is "0.0003".

Step-by-step explanation:

Throughout the early 1980s, reconstructed coagulation factors concentrate extracted from individual blood was collected by hemophiliacs. The concentrate was obtained from either the blood of approximately 1000 donors every lot. The occurrence of hepatitis C throughout donated blood reached 1 in 3000 throughout the early 1980s.

Therefore, the risk though from a single injection of clotting factors, a hemophiliac would contracted hepatitis C seems to be:

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