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.

Example Input: Each banana costs $ 5 . How much do 4 bananas cost ?
Example Output: 20

Example Input: Carlos has 58 blocks . He gives 21 to Rachel . How many blocks will Carlos have ?
Example Output: 37

Example Input: There are 64 pigs in the barn . Some more come to join them . Now there are 86 pigs . How many pigs came to join them ?
Example Output:
22