A matchbox is a cuboid whose length is 5 cm, width 3 cm, and height 2 cm. Pack 10 boxes of matches together to form a large cuboid. How to pack the most economical wrapping paper? (Please note by calculation, overlap of wrappers is ignored)
一个火柴盒的形状是长方体，它的长是5厘米，宽是3厘米，高是2厘米．把10盒火柴包装在一起，形成一个大长方体．怎样包装最省包装纸？(请通过计算说明，包装纸的重叠部分忽略不计)
<gadget id="calculator">5 * 2 * 5 * 2</gadget>
<output>100</output>

<gadget id="calculator">2 * 5 * 2 * 5 * 2</gadget>
<output>200</output>

<gadget id="calculator">100 + 200 + 100</gadget>
<output>400</output>

<result>400</result>