Just replace your paragraph with the following paragraph. The reason is that the variable type is wrong

.Assembly window assembly 1

.Subroutine_button 1 _Clicked

.Local variable variable 1, double precision decimal type

.Local variable variable 2, double precision decimal type

.Local variable variable 3 , double precision decimal type

Variable 1 = to the numerical value (edit box 1. content)

Variable 2 = to the numerical value (edit box 2. content)

Variable 3 = to the value (edit box 1. content) + to the value (edit box 2. content)

edit box 3 content = to text (variable 3)