You are provided with an arithmetic question. Your task is to compute the solution using the given arithmetic operations. The only arithmetic operators needed to answer the questions are'+'(addition) and'-'(subtraction). The answer should be correct to one decimal place.
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Question: Tim's cat had kittens. He gave 3 to Jessica and 6 to Sara. He now has9 kittens. How many kittens did he have to start with?

Answer: 18.0


Question: There are 33 oak trees currently in the park. Park workers had to cutdown 18 oak trees that were damaged. How many oak trees will bein the park when the workers are finished?

Answer: 15.0


Question: At the hardware store, 0.2 the nails are size 2d and 0.5 the nails are size 4d. What fraction of the nails are either size 2d or 4d?

Answer:
0.7