A small right-angled triangle flag made of paper, with a base of 15 cm and a height of 18 cm, how many square centimeters of this kind of paper is needed to make 12 such small flags?
一面用纸做成的直角三角形小旗，底15厘米，高18厘米，做12面这样的小旗，至少需要这种纸多少平方厘米？
<gadget id="calculator">18 / 2</gadget>
<output>9</output>

<gadget id="calculator">15 * 9 * 12</gadget>
<output>1_620</output>

<result>1_620</result>