To process a cuboid iron sheet bucket with a length of 25cm, a width of 16cm, and a height of 3dm, at least how many dm**2 iron sheets should be used.
加工一个长方体铁皮水桶，长25cm，宽16cm，高3dm，至少要用多少dm**2铁皮．
<gadget id="calculator">25 / 10</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">16 / 10</gadget>
<output>8/5 = around 1.6</output>

<gadget id="calculator">(5/2) * (8/5)</gadget>
<output>4</output>

<gadget id="calculator">(5/2) * 3</gadget>
<output>15/2 = around 7.5</output>

<gadget id="calculator">(8/5) * 3</gadget>
<output>24/5 = around 4.8</output>

<gadget id="calculator">4 + (15/2) + (24/5)</gadget>
<output>163/10 = around 16.3</output>

<gadget id="calculator">(163/10) * 2</gadget>
<output>163/5 = around 32.6</output>

<result>163/5 = around 32.6</result>