A piece of rectangular paper with a length of 30 cm and a width of 18 cm, if it is cut into small squares of the same size and there is no surplus, how many pieces can be cut at least?
一张长方形纸，长30厘米，宽18厘米，把它截成同样大小的小正方形且没有剩余，最少可裁多少个？
<gadget id="calculator">30 * 18</gadget>
<output>540</output>

<gadget id="calculator">6 * 6</gadget>
<output>36</output>

<gadget id="calculator">540 / 36</gadget>
<output>15</output>

<result>15</result>