Answer:
70
Step-by-step explanation:
Given that:
There are twelve (12) lines in a direction and another nine 9 lines in another direction.
If we draw the above illustration out, we will realize that we will have 11 squares by 8 squares.
i.e these 11 squares are 11 inches apart.
Hence, the length of their grid = 11 inches × 11 inches = 121 inches²
Thus, for 12 in by 12 in tiles; we will have:
=
=
This implies that there are 10 files with just inch gap in length.
Similarly, for 8 squares and 11 inches apart;
The width = 8 inches × 11 inches = 88 inches²
Thus; the 12 in tiles needed =
=
It signifies that there are 7 tiles with inch gap in width.
Thus, the least number of tiles required = 10 × 7 = 70