将一个值与Codeigniter中的两列进行比较

I Have Average Suppose its 38% Then I have Values in Codeigniter LIke this

mark_from   mark_to         Remarks
0                9          Failed
10               19         Also failed
89               99         Excellent

I Have used this Query

$remarks = $this->db->select('remark')->where('mark_from >=',$average)->where('mark_to <=',$average)->get('remarks')->result_array();

Think out of the box:

$this->db->select('remark')
         ->where((int) $average.' BETWEEN mark_from AND mark_to')
         ->get('remarks');