Use square floor tiles with a side length of 30 cm to pave a sidewalk with a length of 18 meters and a width of 3 meters. Each brick is 6 yuan. How much is the minimum cost?
用边长为30厘米的正方形地砖铺一段长18米，宽3米的人行道路面，每块砖6元，至少需要多少元？
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">(3/10) * (3/10)</gadget>
<output>9/100 = around 0.09</output>

<gadget id="calculator">3 / (9/100)</gadget>
<output>100/3 = around 33.333333</output>

<gadget id="calculator">18 * (100/3) * 6</gadget>
<output>3_600</output>

<result>3_600</result>