using the period as a decimal point in a created virtual keypad

I have created a virtual numeric keypad using objects with the following java script:

var player = GetPlayer();
var add7 = player.GetVar("namefill") + "7";
player.SetVar("namefill", add7);  

I would like to use the period to use it as a decimal point. I am putting the keypad inputs into a project variable text field. Everything works great I just can't set the decimal point for values between 0-100 with 2 place decimal resolution. Below is the project published file so you can see what I am doing. Any help with the java script for this would be appreciated. Thank you.

Numeric Keypad | Review 360 (articulate.com)