instruction:
You are given a math word problem and you are supposed to apply a single mathematical operator like addition, subtraction, multiplication, or division on the numbers embedded in the text to answer the following question and then only report the final numerical answer.
question:
maria was buying dvds of her old favorite tv series . she bought 8 dvds at the store and she bought 2 online . how many dvds did she buy total ?
answer:
10

question:
even the chipmunks are trying to get away to find other warmer places to stay . if 21 chipmunk families were left from the original 86 families how many chipmunk families went away ?
answer:
65

question:
while playing a game edward had 15 lives . he lost 8 lives on a hard level . how many lives does he have left ?
answer:
7