she need 432 tiles because 6 feet is 72 inches and 8 feet equals 96 inches so we divide 72 by 4 to get 18 and 96 by 4 to get 24 the since there are 18 rows of ties with each row containing 24 tiles we multiply 24 by 18 and get 432 which means she will need 432 4 inch tiles. i really hope this helps.