A piece of red cloth is 18 meters long and 0.9 meters wide. If you want to make an isosceles right-angled triangle with a right-angled side of 0.9 meters, how many isosceles right-angled triangles can you make?
一块红布，长18米，宽0.9米，要做成直角边是0.9米的等腰直角三角巾，可以做多少块等腰直角三角巾？
<gadget id="calculator">18 * 0.9</gadget>
<output>16.2</output>

<gadget id="calculator">0.9 * 0.9</gadget>
<output>0.81</output>

<gadget id="calculator">16.2 / 0.81</gadget>
<output>20</output>

<gadget id="calculator">20 * 2</gadget>
<output>40</output>

<result>40</result>