

<?php
$c1 = "29:00:00";
$c2 = "05:10:00";
$Newc1 = mktime($c1);
$Newc2 = mktime($c2);
$NewTime = $Newc1 + $Newc2;
echo date ('G:i:s', $NewTime);
?>
<?php
$c1 = "29:00:00";
$c1 = explode(':', $c1);
$c2 = "05:10:00";
$c2 = explode(':', $c2);
$Newc1 = mktime($c1[0],$c1[1],$c1[2]);
$Newc2 = mktime($c2[0],$c2[1],$c2[2]);
$NewTime = $Newc1 + $Newc2;
echo date ('G:i:s', $NewTime);
?>




