Given the rationale, provide a reasonable question and answer. Step-by-step reasoning process: Since each chapter of the book has 40 pages, Mitchell had read 10 * 40 = 400 pages from the first ten chapters. After reading 20 pages of the eleventh chapter, the total number of pages that Mitchell had read is 400 + 20 = 420. The next two chapters that she read had 2 * 40 = 80 pages. In total, Mitchell read 420 + 80 = 500 pages of the book that day.
 The question and answer:
Studying for her test, Mitchell had read ten chapters of a book before 4 o'clock. When it clocked 4, Mitchell had read 20 pages of the 11th chapter of the book she was studying from. After 4 o'clock, she didn't read the remaining pages of chapter eleven but proceeded and read 2 more chapters of the book. If each chapter in the book had 40 pages, calculate the total number of pages that Mitchell had read altogether?
The answer is 500