instruction:
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.
question:
Bobby has 142 books . Kristi has 78 books . How many more books does Bobby have than Kristi ?
answer:
64


question:
There are 47 eggs in a box . Harry takes 5 eggs . How many are left ?
answer:
42


question:
Kimberly has 5 Skittles . She buys 7 more . Later , Kimberly buys 18 oranges at the store . How many Skittles does Kimberly have in all ?
answer:

12


