A steel bar is divided into three sections, the first section is the full length (1/3), the second section is the full length (2/5), and the third section is 8m long. How long is this steel bar?
一根钢筋分成三段，第一段为全长的(1/3)，第二段为全长的(2/5)，第三段长8m，这根钢筋有多长？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (1/3) - (2/5)</gadget>
<output>4/15 = around 0.266667</output>

<gadget id="calculator">8 / (4/15)</gadget>
<output>30</output>

<result>30</result>