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 Input:
There are 139 erasers and 118 scissors in the drawer . Jason placed 131 erasers in the drawer . How many erasers are now there in total ?

Ex Output:
270

Ex Input:
Rachel bought 7 new chairs and 3 new tables for her house . If she spent 4 minutes on each piece furniture putting it together , how many minutes did it take her to finish ?

Ex Output:
40

Ex Input:
Keith found 6 seashells , Jessica found 8 seashells , and Tim found 7 seashells on the beach . When they cleaned them , they discovered that 3 were cracked . How many seashells did they find together ?

Ex Output:
21