Set up the methods to equal each other:
[tex]47,085 + 11.25x = 19,577 + 24.25x[/tex]
The numbers will represent the one-time fixed costs, and the numbers with variables will represent variable costs.
Subtract 19,577 from both sides:
[tex]27508 + 11.25x = 24.25x[/tex]
Subtract 11.25x from both sides:
[tex]27508 = 13x[/tex]
Divide both sides by 13 to get x by itself:
[tex]x = 2116[/tex]
The two methods will cost the same if 2116 books are produced.