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.

[EX Q]: Megan 's class is going on a field trip to the zoo . If each van can hold 5 people and there are 25 students and 5 adults going , how many vans will they need ?
[EX A]: 6

[EX Q]: Jason joined his school 's band . He bought a flute for $ 142.46 , a music stand for $ 8.89 , and a song book for $ 7 . How much did Jason spend at the music store ?
[EX A]: 158.35

[EX Q]: Anne weighs 67 pounds . Douglas weighs 52 pounds . How much heavier is Anne than Douglas ?
[EX A]:
15