When I pick up a random book, just to have something to read it could take me ages till I finish it or just leave it somewhere in the middle and never (never say never) get back to it. I'm currently in the middle for 3-4 books, which for some reason I can't continue them even though I want to. The Count of Monte Cristo, Passions (by Jane Austen) and others. When the book is readable and I can read through it easily it takes me about a week and only because I'm always busy and don't have time to read. When I was single and carefree I could finish a book in 2 days! The last book I read took me over a month(!) to finish.