road is (7/8) kilometers long and will be repaired in three days, (3/8) kilometers will be repaired on the first day, (2/5) kilometers will be repaired on the second day, and a fraction of a kilometer will be repaired on the third day ?
一条路长(7/8)千米三天修完，第一天修了(3/8)千米，第二天修了(2/5)千米，第三天要修几分之几千米？
<gadget id="calculator">7 / 8</gadget>
<output>7/8 = around 0.875</output>

<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

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

<gadget id="calculator">(7/8) - (3/8) - (2/5)</gadget>
<output>1/10 = around 0.1</output>

<result>1/10 = around 0.1</result>