The engineering team repaired a canal. On the first day, it built the full length (1/3), on the second day it built 30 meters, and in two days it built the full length (1/2). How many meters is this canal?
工程队修一条水渠，第一天修了全长的(1/3)，第二天修了30米，两天共修了全长的(1/2)，这条水渠全长多少米？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/2) - (1/3)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">30 / (1/6)</gadget>
<output>180</output>

<result>180</result>