More function troubles

Still strugglin through with the PHP stuff...... I keep getting a Warning: Missing argument 2 for check_zero() in c:\Inetpub\wwwroot\ecurry\order.php on line 5 if ($name == "andrea") { $experience= 2; $age= 24 check_zero($age, $experience); } This calls check which is at the very top of the page function check($age, $experience){ // this is line 5 $total= $age * $experience; if (total > 50) { echo "you have enough experience"; } } What is the usual reason for this? Thanks for your replies, AD