The answer will depend on the size of the patio slabs.
The answer will vary slightly depending on assumptions: will the slabs have a space between them, and will you be cutting the slabs to fill fractions. 21 feet is equal to 14.2 of the 450 mm slabs. 19 feet is equal to 12.9 of the slabs. To complete the rectangular area, 14.2 x 12.9 = 183 slabs.
140
To find out how many 18-inch by 18-inch slabs fit into a 31-foot by 9-foot area, first convert the dimensions to inches. The area of the space is 31 ft × 12 in/ft = 372 inches and 9 ft × 12 in/ft = 108 inches, giving a total area of 372 inches × 108 inches = 40,176 square inches. The area of one slab is 18 inches × 18 inches = 324 square inches. Dividing the total area by the area of one slab, 40,176 ÷ 324, results in approximately 124 slabs.
To determine how many slabs fit in an area of 600 x 600 cm, you need the size of each slab. If we assume each slab is 60 x 60 cm, then each slab covers an area of 3,600 cm². The total area of 600 x 600 cm is 360,000 cm². Dividing 360,000 cm² by 3,600 cm² gives you 100 slabs.
The answer will depend on the size of the patio slabs.
The answer will vary slightly depending on assumptions: will the slabs have a space between them, and will you be cutting the slabs to fill fractions. 21 feet is equal to 14.2 of the 450 mm slabs. 19 feet is equal to 12.9 of the slabs. To complete the rectangular area, 14.2 x 12.9 = 183 slabs.
20 I believe
You will need 63 44cm x 44cm slabs to cover that area.
If most of the off-cuts are also used then you will need 315 slabs. Otherwise you will need a lot more.
140
To determine how many 450mm x 450mm slabs are needed to cover a 5ft x 4ft area, first convert the dimensions to millimeters: 5ft is approximately 1524mm and 4ft is approximately 1219mm. The area of the space is 1524mm x 1219mm = 1,860,756 mm². Each slab covers an area of 450mm x 450mm = 202,500 mm². Dividing the total area by the area of one slab gives you approximately 9.2, so you will need 10 slabs to cover the area completely.
To determine how many 400x400 mm slabs fit in a square meter, first convert the dimensions of the slab to meters: 400 mm is 0.4 m. The area of one slab is 0.4 m x 0.4 m = 0.16 m². Since one square meter equals 1 m², you can fit 1 m² / 0.16 m² = 6.25 slabs. Therefore, you can fit 6 slabs, with a little area left over.
150 sq ft = 13.94 sq metres, approx. That area would require 68.8 or 69 slabs. However, this assumes that the area to be covered is "well-behaved" and that wastage is kept to a minimum.
220 should do it.
40 slabs
42 slabs...