We need to set up an equation.
297.20 is our total, so it goes after the equal sign.
c is the amount per book.
20 is the amount of books.
297.20 = 20c
Now we need to isolate the variable to solve for c.
Do the inverse operation.
20c = 297.20
20c/20 = 297.20/20
c= 297.20/20
c= 14.86
Our final answer: Each book costs 14.86 dollars