instruction:
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.
question:
Ceasar needs to read a 563 page book for school . He has already read 147 pages . How many pages does he have left to read ?
answer:
416


question:
Joan has 40 blue balloons Melanie has 41 blue balloons . How many blue balloons do they have in total ?
answer:
81


question:
29 birds were sitting in a tree . Some more fly up to the tree . Then there were 42 birds in the tree . How many more flew up to the tree ?
answer:

13