Any multiple of 20 that is greater than 400. If the multiple is 400 or fewer then the length of the rectangle will be less than (or equal to) its width which contradicts the definition of the length as the longer side of a rectangle.
2
12
36
5 x 8 = 40, so 40 tiles are in this rectangle.
4 times the number of tiles in the length of the rectangle.
2
60
12
25
36
Twelve.
5 x 8 = 40, so 40 tiles are in this rectangle.
one tiles
3*5 = 15 tiles.
4 times the number of tiles in the length of the rectangle.
How long is the rectangle? If the rectangle is only one tile long, then it will take 20 tiles.
at least 650 tiles with increments of 25 depending on how long a rectangle.