How can I make the Form Calculation Widget return a value?

I am trying to have a value calculated based on the response to 2 fields however all it does is input the formula in the return field instead of the answer.

I am looking at household size (number field) and total income (Form Calculation Field) and using the following formula: Income/((12140*(household size-1))*100). 

If a person lists a household of 1 and income of 1000 the return I should get would be 8. What I'm actually getting is 1000/((12140*(1-1)*100).

I've tried doing it both in the Form Calculations Widget and also as a Condition and get the same result.  I can't figure out what I'm doing wrong.

If the target answer/output is 8, then the calculation should be like this: (1000/((12140*1)-1))*100

Outcome/Result:

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