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.
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Question: i put another number into my machine . the machine added 15 and then subtracted 6 the number 35 came out of the machine . what number did i put in ?

Answer: 26

Question: randy has 78 blocks . he uses 19 blocks to build a tower . how many blocks are left ?

Answer: 59

Question: haley collected 9 cans for recycling . if she put 7 cans in 1 bag what 's the difference between the number of recycling cans that haley collected and put in the bag ?

Answer:
2