A room measuring 35/3m by 63/8m is to be tiled with square tiles of maximum size so that the tiles fit the dimensions of the room exactly.

35/3  * 8/8 =  280/24

63/8  * 3/3 = 189/24

GCF of 280 ND 189 IS ?   

    Answer ' 7'

so use 7/24  x 7/24 m tiles         280/24 x 189/24 = 91.875 sq m

                                                               91.875m^2/ (7/24 * 7.24)m^2/tile = 1080 tiles   (40 x 27 tiles)