It takes 30 days for teams A and B to complete the excavation of a canal. Now after 12 days of joint excavation, the remaining team B has dug another 24 days to complete it alone. How many days will it take for team A to dig this canal alone?
一条水渠，甲、乙两队合挖需30天完工，现在合挖12天后，剩下的乙队单独又挖了24天完成，这条水渠由甲队单独挖需多少天？
<gadget id="calculator">1 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">(1/30) * 12</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(3/5) / 24</gadget>
<output>1/40 = around 0.025</output>

<gadget id="calculator">(1/30) - (1/40)</gadget>
<output>1/120 = around 0.008333</output>

<gadget id="calculator">1 / (1/120)</gadget>
<output>120</output>

<result>120</result>