A steel pipe, cut off the full length (1/10) for the first time, and cut off the full length (1/5) for the second time, what fraction is left?
一根钢管，第一次截去全长的(1/10)，第二次截去全长的(1/5)，还剩下几分之几？
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/10) + (1/5)</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10)</gadget>
<output>7/10 = around 0.7</output>

<result>7/10 = around 0.7</result>