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Math is ok.
The first question, from the area formula of a circle, we can know that the area of paper is 8X8Xπ=64π, and then from the area formula of a rectangle, we can know that the length is a=64π÷8=8π ≈25. 12, and the area is 200.96, which is the same as the circle.

This question is unconventional. The main test is the imagination of the questioner. When we put a circle into a rectangle, we can pretend to divide the circle into countless sectors with a radius of 8CM, and then think about what the radius and width are. Of course, it is a circle, so the above 25. 12 holds.

I didn't see the picture in the second question, and then it was estimated to be 4X25+2x30+2X20+40=240.

This is the answer to the question. Be sure to give it a good review, dear. If you don't understand anything, you can continue to ask.