If a circle is drawn inside a rectangle with a length of 6 cm and a width of 4 cm, what is the longest radius of the circle in cm?
在一个长6厘米、宽4厘米的长方形内画一个圆，那么这个圆的半径最长是多少厘米．
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<result>2</result>