For a drawer with a length of 6dm, a width of 4dm, and a height of 1.5dm, at least how many dm of wooden boards should be used**2.
一个长6dm，宽4dm，高1.5dm的抽屉，至少要用木板多少dm**2．
<gadget id="calculator">6 * 1.5</gadget>
<output>9</output>

<gadget id="calculator">4 * 1.5</gadget>
<output>6</output>

<gadget id="calculator">9 + 6</gadget>
<output>15</output>

<gadget id="calculator">15 * 2</gadget>
<output>30</output>

<gadget id="calculator">6 * 4</gadget>
<output>24</output>

<gadget id="calculator">30 + 24</gadget>
<output>54</output>

<result>54</result>