A wire can enclose a circle with a diameter of 5 cm. If it encloses the largest square, what is the side length of the square?
一根铁丝可以围成直径是5厘米的圆，如果把它围成一个最大的正方形，正方形的边长是多少厘米？
<gadget id="calculator">5 / 4</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">3.14 * (5/4)</gadget>
<output>3.925</output>

<result>3.925</result>