gravityform - retrieve multiple check answers "keys" instead of "values"

I need to implement a custom math sum relative to the answers of a multiple checkbox question.

Let's suppose I have a question like this: Question:

• first choice
• second choice
• third choice

If I show values, by default, the value will be equal to the key. so:

• first choice = first choice
• second choice = second choice
• third choice = third choice

Let's suppose I give these 3 answers numeric values, for example:

• first choice = 3
• second choice = 1
• third choice = 5

like this I will be able with a numeric field to make a sum of the values just by calling the mergetags. Let's suppose the above question has ID 26, on my numeric field I will just activate the math calculation and I will have the sum just by using {:26.1} + {:26.2} + {:26.3}

But doing so, on my admin side, when a user submit the form, it will display the numeric values. Let's suppose the user chose answer 1 and answer 3, the output on the admin panel will be something like this:

Question:

3 - corresponding to first choice numeric value

5 - corresponding to third choice numeric value

Doing so I'm not able to see what answer they actually chose, but only the value. Is there any way on the admin side to retrieve the key instead of the value to be able to display the text answer instead of its numeric value?

Thanks