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: While taking inventory at her pastry shop, Kelly realizes that she had 0.4 box of baking powder yesterday, but the supply is now down to 0.3 box. How much more baking powder did Kelly have yesterday?

Answer: 0.1


Question: In one week, Mitch's family drank 0.5 carton of regular milk and 0.1 carton of soy milk. How much milk did they drink in all?

Answer: 0.6


Question: Mary had 8 potatoes in the garden. The rabbits ate 3 of the potatoes. How many potatoes does Mary now have?

Answer:
5.0