Put the circle together into an approximate rectangle. The length of the rectangle is 6.28 decimeters. The area of the circle is______ Square centimeter, perimeter is______ Decimeter | Math enthusiast | Mathematical art

Put the circle together into an approximate rectangle. The length of the rectangle is 6.28 decimeters. The area of the circle is Square centimeter, perimeter is Decimeter

The circumference of the circle: 6.28 × 2 = 12.56 (decimeter); the area of the circle: 3.14 × (12.56 △ 3.14 △ 2) 2 = 3.14 × 4, = 12.56 (square decimeter). Answer: the area of the circle is 12.56 square decimeter, the circumference is 12.56 decimeter. So the answer is: 12.56, 12.56

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