The front wheel of a road roller is 1.5 meters wide, and it advances about 20 meters per minute. How long does it take for this road roller to press a road that is 200 meters long and 3 meters wide?
一台压路机的前轮宽1.5米，每分大约前进20米，这台压路机要压一条长200米，宽3米的路面，大约需要多少时间？
<gadget id="calculator">200 / 20</gadget>
<output>10</output>

<gadget id="calculator">3 / 1.5</gadget>
<output>2</output>

<gadget id="calculator">10 * 2</gadget>
<output>20</output>

<result>20</result>