An iron wire can form an isosceles triangle with a waist length of 15 cm and a base length of 24 cm. If it is changed to an equilateral triangle, how many centimeters is the side length of the equilateral triangle?
一根铁丝可以围成一个腰长15厘米，底长24厘米的等腰三角形，如果改围一个等边三角形，那么等边三角形的边长是多少厘米？
<gadget id="calculator">15 * 2</gadget>
<output>30</output>

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

<gadget id="calculator">54 / 3</gadget>
<output>18</output>

<result>18</result>