Real new.... sub not working correctly.

[Carter and Cathleen]

I'm real new to perl, but here's what I'm doing (The sub isn't working correctly).

########### BEGIN PROGRAM ############

#!/usr/bin/perl

$x = $getnumber;

$y = $getnumber;

$z = $x + $y;

print "$x + $y = $z";

sub getnumber {

    print "Enter a number \n";
    $number = <>;
    chop($number);
    $number
}

############ END PROGRAM ##############

Now when I spit this through I get:

+ = x

I have yet to get a sub to work correctly.  Am I doing something drastically wrong?  
Thanks everyone!

M. Carter Brown