Irrespective of how the books are oriented, the 1st page of every book is page number 1, thus 1+1 = 2.
Solve this puzzle
Erin reads an average of 20 books per year. She read 23, 17, 20, and 19 books in four different years. How many books did Erin read in the 5th year to make it an average of exactly 20.0 per year?