The answer will depend on the size of the patio slabs.
400 at least
23.41 sq m
140
20 ft= 6096 mm (6096 * 6096) / (450 * 450) = 183.512178 184 slabs
The answer will depend on the size of the patio slabs.
20 I believe
400 at least
305.56
23.41 sq m
140
20 ft= 6096 mm (6096 * 6096) / (450 * 450) = 183.512178 184 slabs
You will need 63 44cm x 44cm slabs to cover that area.
42 slabs...
40 slabs
220 should do it.
48+ breakages