I'm trying to use this feature to calculate a cumulative value based on

I'm trying to use this feature to calculate a cumulative value based on the responses to multiple choice questions. For example:

If answer to question 1 is yes, add 1 to TOTAL RISK SCORE

and

if answer to question 2 is yes, add 1 to TOTAL RISK SCORE

and

if answer to question 3 is yes, add 1 to TOTAL RISK SCORE

such that if answers to questions 1, 2, and 3 are all yes, TOTAL RISK SCORE would equal 3 (1+1+1)

I can't get the TOTAL RISK SCORE field to accumulate/add these individual risks - it seems that each one over-writes the others. Is there a proper way to do this where the responses to different questions could add to a certain field and that field will display the sum of all numbers added?

Thank you.

What is the form in question? You need to assign a value to the options of each question: https://www.jotform.com/help/301-How-to-Assign-Calculation-Value 

Then, you just need to add them up(field1 + field2 + field3) in the final calculation.