Given a math word problem, answer the following question. You might need to apply addition or subtraction mathematical operators on the numbers embedded in the text to answer the question and then only report the final numerical answer.
Example: robin bought 11 sodas for her and her friends . if they only drank 3 of them how many extras did she have ?
Example solution: 8
Example explanation: Extra sodas is total - drank = 11-3 = 8

Problem: joshua has 3 toy boxes for his toy cars . he puts in 21 toy cars in the first toy box 31 toy cars in the second toy box and 19 toy cars in the third box . how many toy cars does joshua have together ?

Solution: 71