Since Peter reads three times as fast as Kristin, Kristin will take 18*3 = <<18*3=54>>54 hours to read one book.

Kristin reads half of her books, a total of 20/2 = <<20/2=10>>10 books.

The time Kristin will take to read half of her books is 10*54 = <<10*54=540>>540

# Answer

540
Question:
Peter and Kristin are to read 20 fantasy novels each in a week. Peter can read three times as fast as Kristin. If Peter reads one book in 18 hours, how long will Kristin read half of her books?
Answer:
Let's think step by step.

user
540
Peter and Kristin are to read 20 fantasy novels each in a week. Peter can read three times as fast as Kristin. If Peter reads one book in 18 hours, how long will Kristin read half of her books?
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