375 square feet.
300 square feet. This is an easy calculation - just multiply the length by the width. The answer is the number of square feet.
240 square feet
It is 4 times 15 = 60 square feet
Air conditioner BTUs are recommended based on the square footage of a room. A room that is 20'x28'x15' high has a square footage of 560, as the height is not usually factored in. A room that is 560 square feet should have an AC with at least 18,000 BTUs. Because of your high ceiling, though, consider one with at least 20,000.
The area of all the surfaces in the room is: 2*(27*15 + 15*8 + 8*27) = 2*(405 + 120 + 216) = 2*741 = 1482 sq ft
10-ft x 15-ft = 150 square feet = (16 and 2/3) square yards
It is √(x15), which can be simplified to approx 3.873*√x.
1500 cubic feet, ft3
That's about 23' by 23' or 3 rooms just under 12'x15'. Mentally think of one of the 12'x15' rooms split into the kitchen and bathroom space and some of the other room area should be closet space. If it's a studio, it would be one large room with kitchen and bathroom space.
40'x15' = 600 sq ft = 600/9 sq yards = 66.66... sq yards.
15m x 15m = 225 square meters.