There are two boxes of rectangular candies, the length, width, and height are 15cm, 10cm, and 3cm respectively. They are fully enclosed and packed together with wrapping paper. How to pack the most economical wrapping paper? Please calculate the area of the wrapping paper (the seams are ignored).
有两盒长方形的糖果，长、宽、高分别是15cm、10cm、3cm，用包装纸将它们全封闭包装在一起，怎样包装最节约包装纸？请计算出包装纸的面积(接缝处忽略不计)．
<gadget id="calculator">15 * 10</gadget>
<output>150</output>

<gadget id="calculator">15 * 3</gadget>
<output>45</output>

<gadget id="calculator">10 * 3</gadget>
<output>30</output>

<gadget id="calculator">150 + 45 + 30</gadget>
<output>225</output>

<gadget id="calculator">225 * 2 * 2</gadget>
<output>900</output>

<gadget id="calculator">15 * 10 * 2</gadget>
<output>300</output>

<gadget id="calculator">900 - 300</gadget>
<output>600</output>

<result>600</result>