Answer: Our required probability would be 0.75.
Step-by-step explanation:
Since we have given that
Probability that subject will have been exposed to a certain allergen and experience a reaction to the allergen = 0.60
Probability that subject exposed to the allergen will experience an allergic reaction = 0.80
Let Probability that he will have been exposed to the allergen be 'x'.
By multiplication law of probability, we get that
[tex]0.8x=0.6\\\\x=\dfrac{0.6}{0.8}\\\\x=0.75[/tex]
Hence, our required probability would be 0.75.