Build a road, and there are 70 kilometers left after repairing (5/7). How many kilometers is the total length of this road?
修一条公路，修了(5/7)后还剩70千米，这条路全长多少千米？
<gadget id="calculator">5 / 7</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">1 - (5/7)</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">70 / (2/7)</gadget>
<output>245</output>

<result>245</result>