Answer: The required probability is 22%.
Explanation:
Since we have given that
Percentage of the library books in the fiction are worn and need replacement = 30%
Probability of non fiction holdings are worn = 10%
Probability of books are fiction = 60%
Probability of books are non fiction = 40%
So, Probability that a book chosen at random from this library is worn and needs replacement is given by
P(F).P(F∩W)+P(F').P(F'∩W)

Hence, the required probability is 22%.