A square floor is fitted with rectangular tiles of perimeter 220 cm. Each row carries 20 less tiles than each column. If the length of the floor is 9.6 m; calculate
(a) the dimensions of the tiles.
(b) the number of tiles needed.
(c) the cost of fitting the tiles if the tiles are sold in dozens at Kshs. 1500 per dozen and the labour cost is Kshs. 3000.