Yes, it is almost correct way (you have bad quote order), but functions you are using are depracted. Use mysqli. You should alsu use intval() because user can input text value and it generates error.
$sql = '
SELECT * from table
where match
(keywords)
AGAINST
("'.mysql_real_escape_string($s).'" IN BOOLEAN MODE)
order by date desc
limit '.intval($_GET['number']).',10
';