As shown in the figure, the area of the circle is 21.98 square centimeters, so how many square centimeters is the area of the square?
Let the radius of the circle be r, then R2 = 21.98 △ 3.14 = 7, the area of the square is 2R × 2R = 4r2 = 4 × 7 = 28 (square centimeter). Answer: the area of the square is 28 square centimeter
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