You are given a math word problem and you are supposed to only use subtraction on the numbers embedded in the text to answer the following question and then only report the final numerical answer.

[Q]: Context: Dave had 21 apps on his phone. He added 89 new apps. After deleting some he had 24 left. 

 Question: How many more apps did he add than he deleted?
[A]: 3


[Q]: Context: Josh had 9 marbles in his collection. He lost some marbles. If he has 4 marbles now 

 Question: How many marbles did he lose?
[A]: 5


[Q]: Context: Robin cut off 13 inches of his hair. If his hair was 14 inches long initially 

 Question: How long is his hair now?
[A]:
1