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:
While shopping for music online , Isabel bought 6 country albums and 2 pop albums . Each album came with a lyric sheet and had 9 songs . How many songs did Isabel buy total ?

Ex Output:
72


Ex Input:
A waiter at ' The Greasy Spoon ' restaurant had 29 customers to wait on . During the lunch rush he added another 20 customers . If 34 of the customers did n't leave him a tip , how many customers did leave a tip ?

Ex Output:
15


Ex Input:
At Oliver 's Restaurant a group with 2 adults and 4 children came in to eat . If each meal cost 3 dollars , how much was the bill ?

Ex Output:

18