calc result (always the same,and i change the numbers)

I´ve made a simple calc program, and i have always the same result.

I made the calcls in excel or by hand and they are ok, in MITappInventor dont give error but it's always the same result . 

What i've made wron ? can anyone helpme ?

rendimento_copy1.aia

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I do not know what the calculation should have been, but your calculation always amounts to 8900/10500=0.84761
Maybe it is clear to you when I format the blocks differently (click on a math block and choose external inputs to see it the same way).

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Agree with Ghica. I worked the formula through in a spreadsheet and always got 84.761 - unless textbox 2 and textbox 3 have the same number in which case you get 0/0 = infinity or error

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