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:
At the schools book fair Sam bought 13 adventure books and 17 mystery books . If 15 of the books were used , how many new books did he buy ?
answer:
15

question:
Haley had 27 music files and 42 video files on her flash drive . If she deleted 11 of the files , how many files were still on her flash drive ?
answer:
58

question:
Mary found 45 seashells , Melanie found 23 seashells , and Jason found 32 seashells on the beach . When they cleaned them , they discovered that 31 were cracked . How many seashells did they find together ?
answer:
100