TASK DEFINITION: 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.
PROBLEM: There are 97 erasers in a box . Ernest has 17 erasers in a bag . Mark takes 97 erasers out of the box . How many erasers are left in the box ?

SOLUTION: 0

PROBLEM: A waiter had 9 tables he was waiting on , with 4 women and 3 men at each table . How many customers total did the waiter have ?

SOLUTION: 63

PROBLEM: A neighborhood grocer sells a mix of chocolate and carob candy . The chocolate cost 2.7 dollars a pound and the carob costs 2.55 dollars a pound . If 20 pounds of the chocolate and 40 pounds of the carob candy are used , what is the cost per pound of the mixture in dollars ?

SOLUTION:
2.6