Remove the largest square from a rectangle with a circumference of 40 cm, and the circumference of the remaining figure is 24 cm

Remove the largest square from a rectangle with a circumference of 40 cm, and the circumference of the remaining figure is 24 cm

It needs to be clear: 1. The side length of the largest square is the width of the rectangle; 2. The perimeter of the remaining figure is less than the original perimeter by two widths. Then the width formula of the original rectangle is: (40-24) △ 2 = 8 (CM). According to the original perimeter and the calculated width, the length of the original rectangle can be obtained as follows: 40 △ 2-8 = 12 (...)

There are two pieces of 6 cm long rectangular paper (different width), stacked together (cross), find the perimeter of the stacked figure

24cm
Translate the width to the corresponding overlapping area
Get the complete four lengths
4*6=24cm

There are two identical rectangles, 9 decimeters long and 3 decimeters wide

Rectangle perimeter 2 * (9 + 3) = 24 decimeters
There are 3 * 4 = 12 decimeters that are overlapped or ignored
So perimeter = 24 * 2-12 = 36 decimeters