Team A and Team B build a road at the same time. Team A has completed (2/7) of this road, and Team B has built more (1/4) of this road than Team A. What fraction of this road is left? build?
甲乙两队同时修一条路，甲队完成了这条路的(2/7)，乙队比甲队多修这条路的(1/4)，还剩这条路的几分之几没有修？
<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(2/7) + (1/4) + (2/7)</gadget>
<output>23/28 = around 0.821429</output>

<gadget id="calculator">1 - (23/28)</gadget>
<output>5/28 = around 0.178571</output>

<result>5/28 = around 0.178571</result>