There is a matchbox whose dimensions are: length 5 cm, width 3.6 cm, height 1 cm. How many square centimeters of hard paper are needed to make such a matchbox? (Thickness of cardboard is ignored)
有一种火柴盒它的外形尺寸为：长5厘米、宽3.6厘米、高1厘米．制做这样一个火柴盒至少共需要硬纸多少平方厘米？(硬纸厚度略去不计)
<gadget id="calculator">5 * 3.6</gadget>
<output>18</output>

<gadget id="calculator">5 * 1</gadget>
<output>5</output>

<gadget id="calculator">3.6 * 1</gadget>
<output>3.6</output>

<gadget id="calculator">18 + 5 + 3.6</gadget>
<output>26.6</output>

<gadget id="calculator">26.6 * 2</gadget>
<output>53.2</output>

<result>53.2</result>