You are given a math word problem and you are supposed to apply addition or subtraction mathematical operators on the numbers embedded in the text to answer the following question and then only report the final numerical answer.
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Question: Gwen had 18 math problems and 11 science problems for homework . If she finished 24 of the problems at school , how many problems did she have to do for homework ?

Answer: 5


Question: At the beach , Miki and her sister both built sandcastles and then measured their heights . Miki 's sandcastle was 0.8333333333333334 foot tall and her sister 's was 0.5 foot tall . How much taller was Miki 's sandcastle than her sister 's ?

Answer: 0.3333333333333333


Question: A pet store had 41 siamese cats and 28 house cats . During a sale they sold 15 cats . How many cats do they have left ?

Answer:
54