A library has a collection of 100 historical novels arranged on a shelf. 5 people borrow 2 books each from the shelf on a particular day,  and 20 more books are borrowed from the shelf on the second day. How many books are remaining on the shelf after the second day?
How many books were borrowed on the first day? ** Five people borrowed 5 people * 2 books/person = <<5*2=10>>10 books on the first day.
How many books were borrowed on the second day? ** After the second day, the total number of borrowed books increased to 10 books + 20 books = <<10+20=30>>30 books.
How many books are remaining on the shelf after the second day? ** The total number of books on the shelf after the second day is 100 books - 30 books = <<100-30=70>>70 books
#### 70