The answer will depend on the size of the patio slabs.
Area = 15*25 = 375 square feet
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.
100
As a 18 sq ft room has area equal to 18*144=2592 sq inches, you need 2592/(18*18)=8 18 inch tiles.
The answer will depend on the size of the patio slabs.
20 I believe
You will need 63 44cm x 44cm slabs to cover that area.
The egyptains placed granite slabs outside because it will cover an area bigger than one hundred football fields and standing 450 feet high.
75ft
Area = 15*25 = 375 square feet
A square slab measuring 0.6 metres all round has an area of 0.36 square metres. This means that to cover an area of 24 square metres you will need 66 slabs and 2/3 of a slab. Covering the area may be problematic if 1/3 of a slab and 2/3 of a slab become involved, of lesser fractions, depending on the exact length and width which gave the area of 24 - and if there is a pattern to maintain.
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.
15ft
100
Well, isn't that a happy little question! To cover 55 square meters with 600mm x 600mm slabs, you would need around 192 slabs. It's like painting a beautiful landscape - just measure twice and lay those slabs down gently, and you'll have a lovely space to enjoy!
As a 18 sq ft room has area equal to 18*144=2592 sq inches, you need 2592/(18*18)=8 18 inch tiles.