The length of a rectangle is 10 cm and the width is 8 cm. If you subtract the circumference of a square with a side length of 1 cm from each side of the rectangle, the circumference of the remaining figure will be reduced Which option is 8 cm less, 8 cm more, 4 cm more Explanation

The length of a rectangle is 10 cm and the width is 8 cm. If you subtract the circumference of a square with a side length of 1 cm from each side of the rectangle, the circumference of the remaining figure will be reduced Which option is 8 cm less, 8 cm more, 4 cm more Explanation

unchanged
Because after cutting off the outside, the same length of cut is left

As shown in the picture on the right, a rectangular sheet of iron is 20 cm long, and its four corners minus a square with a side length of 2 cm
Make a cuboid without cover, what is its volume

Side length 20-2x2 = 16 cm
Volume 16x16x2 = 512 CC
If you don't understand this question, you can ask,

Cut off the four corners of a square with a side length of 1 decimeter and the small cube with a side length of 1 cm. What is the perimeter of the remaining figure?
Note: different units

1 × 4 = 4 decimeters
A: the perimeter of the remaining figures is 4 decimeters