You are given a math word problem and you are supposed to apply a single mathematical operators like addition, subtraction, multiplication or division on the numbers embedded in the text to answer the following question and then only report final the numerical answer.

[Q]: Ruby has 63 apples . Emily takes 55 away . How many apples will Ruby have ?
[A]: 8


[Q]: There are 4 walnut trees currently in the park . Park workers will plant 6 walnut trees today . How many walnut trees will the park have when the workers are finished ?
[A]: 10


[Q]: Misha has 34 dollars . How many dollars does she have to earn to have 47 dollars to buy a dog ?
[A]:
13