A steel bar, cut off (7/8) meters for the first time, cut off (3/10) meters more than the second time, leaving (4/5) meters, how many meters is the total length of this steel bar?
一根钢筋，第一次截去(7/8)米，比第二次多截去(3/10)米，还剩(4/5)米，这根钢筋的全长多少米？
<gadget id="calculator">7 / 8</gadget>
<output>7/8 = around 0.875</output>

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

<gadget id="calculator">(7/8) - (3/10)</gadget>
<output>23/40 = around 0.575</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(7/8) + (23/40) + (4/5)</gadget>
<output>9/4 = around 2.25</output>

<result>9/4 = around 2.25</result>