question: Tyler wants to buy a dictionary that costs $18, a dinosaur book that costs $13, and a children's cookbook that costs $8. He has saved $14 from his allowance. If Tyler earns $5 per hour, how many hours does he have to work to afford his books?
answer: Tyler wants to purchase books that cost $18 + $13 + $8 = $<<18+13+8=39>>39.
  Tyler needs $39 and currently has $14, so he needs to earn $39 - $14 = $<<39-14=25>>25.
  Tyler can earn $25 at a rate of $5 per hour by doing 25 / $5 = <<25/5=5>>5 hours of work.
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