3 books with a length of 20 cm, a width of 4 cm, and a thickness of 1 cm, how much wrapping paper is needed to wrap them together?
3本长20厘米，宽4厘米，厚1厘米的书，包在一起至少需要多少包装纸？
<gadget id="calculator">20 * 4 * 2</gadget>
<output>160</output>

<gadget id="calculator">20 * 1 * 3 * 2</gadget>
<output>120</output>

<gadget id="calculator">4 * 1 * 3 * 2</gadget>
<output>24</output>

<gadget id="calculator">160 + 120 + 24</gadget>
<output>304</output>

<result>304</result>