Huanggang small champion third grade mathematics page 49 training homework.
Suppose the side length of the original square is a, the sum of the perimeters of the three squares is 12A, and the perimeter of the rectangle is 8A. (Because the middle four sides are connected together when spelling, it is not included in the perimeter of the rectangle. ) So 12A-8A = 4A = 60cm, that is, a equals 15, and the area of a square is the side length multiplied by the side length =225.