45% of a road has been repaired, and it is still 1.5 kilometers away from the midpoint. How many kilometers is the total length of this road?
一条公路修了45%，这时离中点还有1.5千米，这条公路全长多少千米？
<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">45 / 100</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">(1/2) - (9/20)</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">1.5 / (1/20)</gadget>
<output>30</output>

<result>30</result>