How to assign calculation values to Multiple Choice Field

Is there a way to make one multiple choice option associated with an element, such as having the option to choose a number appear in a multiple choice option? I want to use this to affect pricing, where it would be the set price times the number that is entered.

Are you trying to use multiple choice to calculate values? If yes, then it's to assign numeric values for each option in your multiple choice field. 

Here is the article that explains How-to-Assign-Calculation-Value. 

I hope this helps. Let us know if you need further assistance.