Problem related to search space


In video bhaiya is taking the search space in consideration of 4 student, as 40 is minimum no. of page that the 4th guy will read but during assinging we are only considering 2 guys only even 3 guys are not allowed pls explain

look at the picture carefully
there are 4 books and only 2 students

the worst case occur
when no of student ==no of books i.e no of student =4
in this case ans will be 40