First we need to find the total area of the floor. Dividing the total area of floor by area of one package of tile will give us the number package of tiles that are needed to cover the floor.
The shape of floor is parallelogram with base 17.5 feet and height of 6 feet. Area of parallelogram is the product of its base and height.
So,
Floor Area = 17.5 x 6 = 105 ft²
Area covered by 1 package of tile = 5 ft²
So, number of package of tiles that are needed = 105/5 = 21 package of tiles.
21 packages of tiles will be needed to fully tile the room.