ok i solved with this code
<?php
$somar = mysql_query("SELECT SUM(landingrate) as landingrate FROM `phpvms_pireps` WHERE pilotid=$userinfo->pilotid");
$total = mysql_fetch_array($somar);
$v_total = $total['landingrate'];
$linha = mysql_query("SELECT * FROM `phpvms_pireps` WHERE pilotid=$userinfo->pilotid");
$taxa = mysql_num_rows($linha);
$v_taxa = $taxa;
$media = $v_total/$v_taxa;
$v_media = number_format($media, 0, '.', '');
?>
<?php echo $v_media." ft/min"; ?>
but you can have a table to put our best 10?
thanks for the help