piece of steel, cut off (3/8) meters for the first time, and cut off (3/10) meters for the second time. How many meters is this steel shorter than the original?
一根钢材，第一次截去(3/8)米，第二次截去(3/10)米．这根钢材比原来短了多少米？
<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">(3/8) + (3/10)</gadget>
<output>27/40 = around 0.675</output>

<result>27/40 = around 0.675</result>