A piece of rectangular paper, 5cm long and 4cm wide, cut the largest circle in the rectangle, what is the area of the circle?

A piece of rectangular paper, 5cm long and 4cm wide, cut the largest circle in the rectangle, and the circle with the rectangle width as the diameter is the largest
Therefore: the diameter of the circle is 4cm, the radius is 4 △ 2 = 2cm
Area of circle = 3.14x2 square = 12.56 (square centimeter)

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