Questions & Answers about Boken er verdt prisen.
Because boken is the definite form, meaning the book.
In Norwegian, the definite article is usually attached to the end of the noun instead of appearing as a separate word.
- bok = book
- boken = the book
So Boken er verdt prisen starts with the book, not just book.
For the same reason: prisen is the definite form, meaning the price.
- pris = price
- prisen = the price
So the sentence literally matches The book is worth the price.