The width of a rectangle is 5 centimeters, and the length is 1 centimeter more than three times the width. If a piece of iron wire is used to wrap such a rectangle around, how much length of iron wire is needed?
一个长方形的宽是5厘米，长比宽的3倍多1厘米，用一根铁丝绕这么一个长方形一周，需要多少长的铁丝？
<gadget id="calculator">5 * 3</gadget>
<output>15</output>

<gadget id="calculator">15 + 1</gadget>
<output>16</output>

<gadget id="calculator">16 + 5</gadget>
<output>21</output>

<gadget id="calculator">21 * 2</gadget>
<output>42</output>

<result>42</result>