How to remove an initial value (0) from a "Numeric Entry" field

I ran into this after I'd already placed all of my numeric entry fields in a course. There is also a way to get the default "0"s to go away from existing numeric entry fields without having to "Delete" and then "Ctrl Z" them.

I think I may be re-stating manish's solution, but basically:

1) Double click the numeric entry field's trigger in the trigger panel to pull up the variable assignment pop up

2) Use the dropdown and change the field's variable to "unassigned"

3) Create a new Text variable, name it whatever you want, and leave the default value for it blank

4) Double click the entry field's trigger in the trigger panel again to go back to the variable assignment pop up

5) Assign the new Text variable to the numeric entry field

6) Unfortunately, you have to re-do whatever triggers you had in place that referenced the original Number variable. I also recommend going back into your project variables list and deleting the old (now unused) Number variables, to keep the project file tidy.