Use a piece of iron wire to form a circle with a length of 10 cm. What is the length of the wire in centimeters for a rectangle with a width of 5 centimeters?
用一根铁丝恰好围成一个长10厘米．宽5厘米的长方形，这根铁丝的长度是多少厘米．
<gadget id="calculator">10 + 5</gadget>
<output>15</output>

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

<result>30</result>