The amount of wealth-tax, interest, penalty, fine or any other sum payable, and the amount of refund due, under the provisions of this Act, shall be rounded off to the nearest rupee and, for this purpose, where such amount contains a part of a rupee consisting of paise, then, if such part is fifty paise or more, it shall be increased to one rupee, and if such part is less than fifty paise, it shall be ignored.