The small conference room in the school needs to be paved with floor tiles with a side length of 4 decimeters, and the total is 250. What is the floor area of the school conference room in m**2.
学校的小会议室要铺地砖，用边长4分米的地砖铺，共用250块，学校会议室地面面积为多少m**2．
<gadget id="calculator">4 / 10</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(2/5) * (2/5) * 250</gadget>
<output>40</output>

<result>40</result>