Hello!
Here are two ways to solve this problem. Way 1:
Convert the fraction to a decimal by dividing its numerator by its denominator.
2 ÷ 3 = 0.6666666667
Then, multiply the decimal by the total amount of books.
0.6666666667 × 12 = 8
Way 2:
Divide twelve by the denominator of the fraction, and then multiply it my the numerator.
12 ÷ 3 = 4
12 × 2 = 8
Thus, 8 of the 12 books are science fiction.