60% of the total length of a road has been built. If another 30 meters are repaired, the ratio of the number of meters that have been repaired to the number of meters that have not been repaired is 7:3. How many meters is this road?
修一条路，已修了全长的60%，如果再修30米，这时已修的米数与未修米数的比是7：3，这条路是多少米？
<gadget id="calculator">7 + 3</gadget>
<output>10</output>

<gadget id="calculator">7 / 10</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">60 / 100</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(7/10) - (3/5)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">30 / (1/10)</gadget>
<output>300</output>

<result>300</result>