How many circles with a diameter of 2 cm can be cut from a square of paper with a side length of 4 cm.
一张边长是4厘米的正方形纸最多可以剪出多少个直径是2厘米的圆．
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<result>4</result>