The floor of Xiao Ming's room is a square, if it is paved with floor tiles. Whether you choose a side length of 50cm or a square floor tile of 40cm, it is just covered. How many square meters is the floor of Xiao Ming's room at least?
小明的房间的地面是一个正方形，如果铺上上地砖．无论是选择边长是50cm，还是选择40cm的正方形地砖，都正好铺满．小明的房间的地面至少是多少平方米？
<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">40 / 100 / 100</gadget>
<output>1/250 = around 0.004</output>

<gadget id="calculator">50 * (1/2) * 40 * (1/250)</gadget>
<output>4</output>

<result>4</result>