# math 
  my $x = "016";
  my $y=$x * 10;
  print "y=$y\n";

# eval
  $y = eval( "$x * 10" );
  print "evalled 016 * 10 , y = $y\n";

# eval without leading zero
 $x = "16";
 $y = eval( "$x * 10" );
 print "evalled 16 * 10 , y = $y\n";


me@ramster:~/perl$ ./x.pl
y=160
evalled 016 * 10 , y = 140
evalled 16 * 10 , y = 160