A Mason fixed black tiles of square shape around a square room. there are 21 tiles on each side of the room. How many tiles did he need altogether?
A Mason fixed black tiles of square shape around a square room. there are 21 tiles on each side of the room. How many tiles did he need altogether?
Explanation
Number of tiles on one side of the room = 21 tiles.
Total tiles = B21×4= 84.
Since 4 tiles at each corner are shared by both rows, subtract these: 84−4= 80 tiles.