Frank was reading through his favorite book. The book had 12 pages equally distributed over 4 chapters. It took Frank 45 days to finish the book. How many pages are in each chapter?
1. Frank reads one page per day. 
2. It takes Frank 45 days to finish the book. 
3. Therefore, Frank reads 45 pages in total. 
4. The book has 12 pages equally distributed over 4 chapters. 
5. Therefore, each chapter has 3 pages.