To make a cuboid iron box with a cover, the length is 10 decimeters, the width is 7 decimeters, and the height is 5 decimeters. How many square meters of iron sheet are needed in total?
做一个有盖的长方体铁皮箱，长是10分米，宽是7分米，高是5分米，共需铁皮多少平方米？
<gadget id="calculator">10 * 7</gadget>
<output>70</output>

<gadget id="calculator">10 * 5</gadget>
<output>50</output>

<gadget id="calculator">7 * 5</gadget>
<output>35</output>

<gadget id="calculator">70 + 50 + 35</gadget>
<output>155</output>

<gadget id="calculator">2 / 100</gadget>
<output>1/50 = around 0.02</output>

<gadget id="calculator">155 * (1/50)</gadget>
<output>31/10 = around 3.1</output>

<result>31/10 = around 3.1</result>