Error 1119: Access of possibly undefined property text through a reference with static type String

I have the following code:

var myPercStr = myStr.text;

myPercStr= myPercStr.toString();

var myPerc = Number(myPercStr);

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I am trying to get the value of a text field which is created by the user pushing a pin-pad.  This text field is a string which is joined() from an Array of the sequence of pin-pad entries.  Now my problem is that Flash will not convert the .text text field into a string with which I can use the value to convert to a Number and perform math on it.

Can someone help me with my code?

Sincerely,

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