The floor of the classroom is 6 meters wide, and the length is 3 meters more than the width. If you want to lay floor tiles with a side length of 3 decimeters, at least how many pieces are needed.
教室地面宽6米，长比宽多3米，如果要铺边长3分米的地砖，至少需要多少块．
<gadget id="calculator">6 + 3</gadget>
<output>9</output>

<gadget id="calculator">3 / 10</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">6 / (9/100)</gadget>
<output>200/3 = around 66.666667</output>

<gadget id="calculator">9 * (200/3)</gadget>
<output>600</output>

<result>600</result>