Think about your decision to buy the textbook for this course you paid 225 for the book but you would have been willing to pay 450 to use the book for the semester supposed that at the end of the semester you could keep your textbook or sell it back to the bookstore once you have completed the course the book is worth only 70 to you. The bookstore will pay you 50 % of the Original 225. How much total value have you Gained?