Walk for a while, 20% of the total length is 10 kilometers more in the morning, and (2/7) of the total length is walked in the afternoon, and there are 53 kilometers left. How many kilometers are you walking in the morning?
走一段路，上午走了全长的20%还多10千米，下午走了全长的(2/7)，还剩53千米，求上午走了多少千米？
<gadget id="calculator">10 + 53</gadget>
<output>63</output>

<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 - (1/5) - (2/7)</gadget>
<output>18/35 = around 0.514286</output>

<gadget id="calculator">63 / (18/35)</gadget>
<output>245/2 = around 122.5</output>

<gadget id="calculator">(245/2) * (1/5)</gadget>
<output>49/2 = around 24.5</output>

<gadget id="calculator">(49/2) + 10</gadget>
<output>69/2 = around 34.5</output>

<result>69/2 = around 34.5</result>