How many planks are needed to pave a room floor with a length of 5.5m and a width of 4m by using right-angled triangular planks with a base and a height of 2.5dm?
用底和高都是2.5dm的直角三角形木板，铺一块长5.5m、宽4m的房间地面，需要多少块这样的木板？
<gadget id="calculator">2.5 / 10</gadget>
<output>0.25</output>

<gadget id="calculator">0.25 / 2</gadget>
<output>0.125</output>

<gadget id="calculator">0.25 * 0.125</gadget>
<output>0.03125</output>

<gadget id="calculator">4 / 0.03125</gadget>
<output>128</output>

<gadget id="calculator">5.5 * 128</gadget>
<output>704</output>

<result>704</result>