(3) Subject to subsection (4) or (5), where an applicant is the adult or, as the case may be, one of the adults referred to in the first column of the Schedule, and his assessed monthly income or, as the case may be, the combined assessed monthly income of the 2 or 3 adults living under the same roof is less than the corresponding amount specified in the second column of the Schedule, he shall be entitled to an amount of financial support which will top up for the monthly income so as to reach the amount specified in the second column, or to such other amount as may be prescribed.