Arghh! how can this not be a number?

Hey there, I’'ve hit a bit of a brick wall here. I am passing an array (Ticket) that contains lots of two-digit strings into a function. The function then needs to extract each number and also find the Math.floor/10 of the number.
For some reason I am getting NaN for n but the number appears as expected :
N: NaN number: 49

Here’s my code:

[AS]
n = Math.floor(Ticket*/10);
trace("N: “+n+” number: "+Ticket*);
[AS]

if anyone could help I’d be really grateful.
Thanks!
Schm