It prints what's inside for else,I need to calculate some points,where is the problem.?

Question

<?php
if(isset($_POST['submit'])) {
$AR = $_POST['AR-A']+$_POST['AR-B']+$_POST['AR-C']+$_POST['AR-D'];
$AR/$_POST['AR-N'];
$AR*2;
$FR = $_POST['FR-A']+$_POST['FR-B']+$_POST['FR-C']+$_POST['FR-D'];
$FR/$_POST['FR-N'];
$FR*4;
$EN = $_POST['EN-A']+$_POST['EN-B']+$_POST['EN-C']+$_POST['EN-D'];
$EN/$_POST['EN-N'];
$EN*2;
$PH = $_POST['PH-A']+$_POST['PH-B']+$_POST['PH-C']+$_POST['PH-D'];
$PH/$_POST['PH-N'];
$PH*2;
$M = $_POST['M-A']+$_POST['M-B']+$_POST['M-C']+$_POST['M-D'];
$M/$_POST['M-N'];
$M*7;
$PC = $_POST['PC-A']+$_POST['PC-B']+$_POST['PC-C']+$_POST['PC-D'];
$PC/$_POST['PC-N'];
$PC*7;
$SVT = $_POST['SVT-A']+$_POST['SVT-B']+$_POST['SVT-C']+$_POST['SVT-D'];
$SVT/$_POST['SVT-N'];
$SVT*7;
$TR = $_POST['TR-A']+$_POST['TR-B']+$_POST['TR-C']+$_POST['TR-D'];
$TR/$_POST['TR-N'];
$TR*2;
$DH = $_POST['DH-A']+$_POST['DH-B']+$_POST['DH-C']+$_POST['DH-D'];
$DH/$_POST['DH-N'];
$DH*2;
$II = $_POST['II-A']+$_POST['II-B']+$_POST['II-C']+$_POST['II-D'];
$II/$_POST['II-N'];
$II*2;
$SP = $_POST['SP-A']+$_POST['SP-B']+$_POST['SP-C']+$_POST['SP-D'];
$SP/$_POST['SP-N'];
$SP*2;
$V = $_POST['V-A']+$_POST['V-B']+$_POST['V-C']+$_POST['V-D'];
$V/$_POST['V-N'];
$V*1;
$note= $AR+$FR+$EN+$PH+$M+$PC+$SVT+$TR+$DH+$II+$SP+$V;
$note/30;
echo $note;
}else echo "error"
?>

Answer 1

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