A certain unit wants to make 15 triangular traffic signs with aluminum skin. The bottom of each sign is 0.9 meters and the height is 0.78 meters. If a total of 0.7 square meters of aluminum skin is lost during the production process, how many square meters of aluminum skin is at least required to make these signs?
某单位要用铝皮制作15块三角形交通标志牌，每块标志牌的底是0.9米，高是0.78米．如果在制作过程中一共要损耗0.7平方米的铝皮，制作这些标志牌至少要多少平方米的铝皮？
<gadget id="calculator">0.78 / 2</gadget>
<output>0.39</output>

<gadget id="calculator">0.9 * 0.39 * 15</gadget>
<output>5.265</output>

<gadget id="calculator">5.265 + 0.7</gadget>
<output>5.965</output>

<result>5.965</result>