Bob is tiling the floor of his 12 foot by 16 foot living room. He plans to place one-foot by one-foot square tiles to form a border along the edges of the room and to fill in the rest of the floor with two-foot by two-foot square tiles. How many tiles will he use?
(12×2)+(14×2)=52___the area around the border
1×1=1the area of tiles around the border
52÷1=52number of tiles
(12-2)×(16-2)=140
2×2=4
140÷4=35
52+35=87