calculator

I'm looking for someone who can solve a problem with App Inventor2 (*, -, +, /). 9 + 1 + 3 = 13

And that also indicates, would be friendly if someone could help me :)

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Try these links https://groups.google.com/forum/#!searchin/mitappinventortest/calculator%7Csort:date   and read about the AI2 Math blocks http://appinventor.mit.edu/explore/ai2/support/blocks/math.html  

Yes, you can solve  9 + 1 + 3 = 13

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