There is a small triangular flag with a base of 5 decimeters and a height of 4 decimeters. How many square meters of fabric is needed to make 100 such small flags?
有一个三角形的小旗，底是5分米，高是4分米，做100面这样的小旗，至少要多少平方米的布料？
<gadget id="calculator">5 / 2 / 100</gadget>
<output>1/40 = around 0.025</output>

<gadget id="calculator">4 * (1/40) * 100</gadget>
<output>10</output>

<result>10</result>