To build a waterway, 20% of the total length was built in the first week, and 2/7 of the total length was repaired in the second week. A total of 170 meters was built in two weeks. How many meters is the total length of this road? ．
修一条水路，第一周修了全长的20%，第二周修了全长的(2/7)，两周共修了170米，这条路全长是多少米？．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">(1/5) + (2/7)</gadget>
<output>17/35 = around 0.485714</output>

<gadget id="calculator">170 / (17/35)</gadget>
<output>350</output>

<result>350</result>