The man figured in his mind that he could lay out the floor in a square-shaped room with square tiles, and that he would

The man figured in his mind that he could lay out the floor in a square-shaped room with square tiles, and that he would not need to cut any of them. He first laid tiles around the edges of the room, which took 56 tiles. How many tiles does he need to cover the entire floor?

If it took 56 tiles to cover the edges, we can find 1 side of the room 56/4 = 14
Find the floor area 14 * 14 = 144
Answer: 144 tiles