Math | Riddles and Puzzles comes from Saltuk Emre Gul. There are 60 levels of finding math patterns and sequences.  

At the moment, I'm stuck on level 30 which reads as follows: 126 = 76
132 = 32
208 = 58
261 = "

Never mind, I just got it.
https://itunes.apple.com/us/app/math-riddles-and-puzzles/id1455734504"mt=8

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