how many tiles needed for a side measure of 80 feet and radius of pool of 25 feet

Question

how many square feet of tiles are needed to make the border with a side measure of 80 feet and the radius of the pool its going around is 25 feet

Answer 1

The diameter of the pool is 50ft (twice the radius). The area of the circular pool is about 25²×3.14=1963.5 sq ft. If the tiles surrounding the pool make up a square of side length 80ft, then the area of the square is 80²=6400 sq ft. So the area the tiles need to cover is 6400-1963.5=4436.5 sq ft. Assuming the centre of the pool coincides with the centre of the square, at its narrowest, the border of the tiles will be ½(80-50)=15ft from the pool. Each corner of the tiled square will be 40√2-25=31.6ft (approx) from the edge of the pool.