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.

Input: Consider Input: The schools debate team had 28 boys and 4 girls on it . If they were split into groups of 4 how many groups could they make ?

Output: 8

Input: Consider Input: Lana picked 36 tulips and 37 roses to make flower bouquets . If she only used 70 of the flowers though , how many extra flowers did Lana pick ?

Output: 3

Input: Consider Input: Melanie had 30 baseball cards , and 9 were torn . Sara bought 18 of Melanie 's baseball cards . How many baseball cards does Melanie have now ?
Output: 12