Array.toString still acting like an array

1 
myArray = new Array();
myArray = ["23.55", "100.23", "97.88"];

var wtf:String = myArray.slice(0,1);

wtf.toString;

trace(wtf.length);

I’m trying to get the length of the wtf variable but it keeps tracing out 1 as if it’s counting the length of the sliced array.
Any suggestions?