Express the following statements in linear equations in two variables:
(i) The larger of two supplementary angle exceeds the smaller by \(18\) degrees.
(ii) \(7\) audio cassettes and \(3\) video cassettes cost for \(Rs. 1110\)
(iii) When both the numerator and denominator decrease by \(6\), then the denominator becomes \(12\) times the numerator.