A triangle is surrounded by a wire with a length of 1 meter. One side of the triangle is (2/5) meters and the other side is (1/4) meters. How long is the third side?
用一根长1米的铁丝围了一个三角形，量得三角形的一边是(2/5)米，另一边是(1/4)米，第三边长多少米？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (2/5) - (1/4)</gadget>
<output>7/20 = around 0.35</output>

<result>7/20 = around 0.35</result>