What changes were made to Paragraph 9 in its application to the States of Tripura and Mizoram by the Sixth Schedule to the Constitution (Amendment) Act, 1988?
The changes made to Paragraph 9 in its application to the States of Tripura and Mizoram by the Sixth Schedule to the Constitution (Amendment) Act, 1988 are:

- Insertion of a new sub-paragraph (3) after sub-paragraph (2), which states that "The Governor may, by order, direct that the share of royalties to be made over to a District Council under this paragraph shall be made over to that Council within a period of one year from the date of any agreement under sub-paragraph (1) or, as the case may be, of any determination under sub-paragraph (2).".