to determine the probability of getting a non-fiction book we need to find the coefficient between the number of non-fiction books and the total number of books. The total number of books is:
[tex]\begin{gathered} N_B=200+300+250+250 \\ N_B=1000 \end{gathered}[/tex]Now we find the probability:
[tex]P=\frac{250}{1000}=0.25[/tex]The probability as a percentage is 25%