Divide a circle into several equal parts first, and then put together an approximate rectangle. It is known that the perimeter of this approximate rectangle is 8.28 cm, what is the radius of this circle?
将一个圆先等分成若干份，再拼成一个近似长方形．已知这个近似长方形的周长是8.28厘米，这个圆的半径是多少？
<gadget id="calculator">1 + 3.14</gadget>
<output>4.14</output>

<gadget id="calculator">8.28 / 2 / 4.14</gadget>
<output>1</output>

<result>1</result>