How many circles can be drawn with a radius of 1.5 cm on a square paper with a side length of 18 cm? (both sides can be painted)
在一张边长是18厘米的正方形纸上，画半径是1.5厘米的圆，最多可以画几个？(正反面都可以画)
<gadget id="calculator">1.5 * 2</gadget>
<output>3</output>

<gadget id="calculator">18 / 3</gadget>
<output>6</output>

<gadget id="calculator">6 * 6 * 2</gadget>
<output>72</output>

<result>72</result>