The first thing you need to do is convert the width and length to feet, since it is currently in yards, but Lucas is buying 1 foot tiles. Since one yard equals 3 feet, you would multiply the sides by 3 to convert the side lengths to feet. This would give you the dimensions in feet which are 12 by 15. Then, since the problem is looking for the amount of tiles to cover the rectangular room, you would multiply the dimensions 12 and 15, to get you to your answer 180 tiles.
